Application guidelines -...

40
Danfoss scroll for refrigeration LLZ013 to 034 Low temperature 50 - 60 Hz - R404A - R507 Application guidelines http://cc.danfoss.com

Transcript of Application guidelines -...

Page 1: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Danfoss scroll for refrigeration LLZ013 to 034 Low temperature50 - 60 Hz - R404A - R507

Application guidelines

http://cc.danfoss.com

Page 2: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,
Page 3: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Content

3FRCC.PC.025.A6.02

Features ............................................................ 4

Scroll compression principle .......................... 5The scroll compression process ......................................5Theory of economized cycle ............................................5

Compressor model designation ..................... 6Nomenclature ........................................................................6Label...........................................................................................6

Technical specifications .................................. 7Model with economizer .....................................................7Model without economizer ..............................................7Model with economizer .....................................................8Model without economizer ..............................................8Model with economizer R404A/R507 ...........................9Model with economizer R404A/R507 ...........................9Model without economizer R404A/R507 ................. 10Model without economizer R404A/R507 ................. 10

Dimensions ..................................................... 11LLZ013-015-018 ....................................................................11LLZ024 .................................................................................... 12LLZ034 .................................................................................... 13Oil sight glass ....................................................................... 14Schrader................................................................................. 14Suction and discharge connections ........................... 14

Electrical data, connections and wiring ...... 15Motor voltage ...................................................................... 15Wiring connections ........................................................... 15IP rating .................................................................................. 15Three phase electrical characteristics ........................ 16LRA (Locked Rotor Amp) ................................................. 16MCC (Maximum Continuous Current) ........................ 16Max Oper. A (Maximum Operating Amp) ................. 16Winding resistance ............................................................ 16Electrical wiring diagram ................................................ 17Internal motor protection............................................... 17Phase sequence and reverse rotation protection . 17Voltage imbalance ............................................................ 17

Approvals and certifications ......................... 18Approvals and certificates .............................................. 18Conformity to directives ................................................. 18Internal free volume ......................................................... 18

Operating conditions .................................... 19Refrigerant and lubricants .............................................. 19Motor supply ....................................................................... 19Compressor ambient temperature ............................. 19Application envelope ....................................................... 20Maximum discharge gas temperature ...................... 21High and low pressure protection .............................. 22On/off cycling (cycle rate limit) ..................................... 22Suction pressure protection ......................................... 22

System design recommendations ................ 23General ................................................................................... 23Essential piping design recommendations ............. 23Economizer selection ....................................................... 24Refrigerant charge limit .................................................. 25Off-cycle migration ........................................................... 25Liquid flood back ............................................................... 27

Specific application recommendations ....... 28Low ambient application ................................................ 28Scroll and reciprocating .................................................. 28Low load operations ......................................................... 29Brazed plate heat exchangers ....................................... 29Water utilising systems .................................................... 29Defrost cycle ........................................................................ 29

Sound and vibration management .............. 30Starting sound level .......................................................... 30Running sound level ......................................................... 30Stopping sound level ....................................................... 30Sound generation in a refrigeration system ........... 30Compressor sound radiation ......................................... 30Mechanical vibrations ...................................................... 31Gas pulsation ....................................................................... 31

Installation ...................................................... 32System cleanliness ............................................................. 32Compressor handling and storage ............................. 32Compressor mounting ..................................................... 32Compressor holding charge .......................................... 32Vacuum evacuation and moisture removal ............. 33Liquid line filter driers ...................................................... 33Refrigerant charging ......................................................... 33Insulation resistance and dielectric strength .......... 33

Ordering information and packaging ......... 34Packaging..............................................................................34Packaging details ...............................................................34Single pack ........................................................................... 35Industrial pack ..................................................................... 35

Spare parts and accessories .......................... 36Crankcase heater ................................................................ 36Discharge temperature protection ............................. 36Magnetic discharge non return valve ........................ 36Magnetic discharge non return valve ........................ 36Lubricant ............................................................................... 36Mounting hardware .......................................................... 37IP54 upgrade kit ................................................................ 37Acoustic hood .................................................................... 37

Application Guidelines

Page 4: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Features

Danfoss scroll compressor for refrigeration, LLZ, with its unique scroll design and manufacturing process flexibility, offers a highly efficient solution for demanding refrigeration applications.

This new family of refrigeration scroll compressors includes 5 sizes of low temperature scroll compressors designed for commercial refrigeration applications. These compressors are engineered for refrigeration and offer cooling capacity from 5 to 12 kW (4 to 10 HP) at common voltages and frequencies as well as any of the common refrigerants (R404A - R507).

In the LLZ range of refrigeration scrolls, the compressors can work with the economizer line activated, named as economized compressor; or with the economizer line disabled, named as standard compressor. The economized compressor has been developed to provide improved performance and an enlarged operating envelope in refrigeration applications. The economized compressor system presents benefits over standard refrigeration compressor systems of equivalent horse power due to the following:

• Capacity improvement: The capacity is improved without increasing compressor displacement, as it is increased by further increasing system subcooling with a heat exchanger acting as an economizer

(connected to the compressor economizer line). Furthermore a smaller economized compressor can be used to achieve the same capacity as a larger standard compressor, leading to cost advantages.

• Efficiency improvement: With a suitable sized heat exchanger, the efficiency improves due to the fact that the gain in capacity is greater than the increase in power that the compressor consumes.

• Enlarged operating envelope: The injection of vapour through the economizer line will reduce the discharge temperature and therefore enlarge the operating envelope based on the same suction status.

4 FRCC.PC.025.A6.02

Application Guidelines

Page 5: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Scroll compression principle

Danfoss scroll compressors are manufactured using the most advanced machining, assembly, and process control techniques. In the design of both the compressor and the factory, very

high standards of reliability and process control are first priority. The result is a highly efficient product with the highest reliability obtainable, and a low sound level.

The below schematic shows a system configuration with a heat exchanger acting as an economizer for economized cycle (12345671). The economizer is used to provide subcooling to the refrigerant leaving the condenser before it enters into the evaporator. This subcooling process provides an increased capacity gain for the system. Meanwhile, another small amount of

refrigerant leaving the condenser goes through the expansion device and is then evaporated and superheated. The superheated refrigerant is then injected into the mid-compression cycle of the compressor and compressed together with the suction flow. The injected vapour also provides cooling and therefore lowers the discharge temperature.

The entire scroll compression process is illustrated below. The centre of the orbiting scroll traces a circular path around the centre of the fixed scroll. This movement creates compression pockets between the two scroll elements.

Low pressure suction gas is trapped within each crescent-shaped pocket as it forms; continuous motion of the orbiting scroll serves to seal the pocket, which decreases in volume as the

pocket moves towards the centre of the scroll set with a corresponding increase in gas pressure. Maximum compression is achieved, as the pocket reaches the discharge port at the centre.

Scroll compression is a continuous process: when one pocket of gas is being compressed during the second orbit, another gas quantity enters a new pocket formed at the periphery, and simultaneously, another is being discharged.

The scroll compression process

SUCTION

COMPRESSION

DISCHARGE

Theory of economized cycle

Pi

P

h

i

m

m+i

1 2

34

576

Economizer cycle 12345671Economizer system configuration

5FRCC.PC.025.A6.02

Application Guidelines

Page 6: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Compressor model designation

Label

Nomenclature

Serial number

Type FeaturesMotorSize

L LZ Q 9T 4 L013Application

L: low temperature refrigeration

Family, Refrigerant & lubricantLZ: R404A - R507, PVE lubricant

Nominal capacityIn thousand Btu/h at 60 Hz,ARI, LBP conditions

Model variationT: design optimised for refrigeration

Motor protectionL: internal motor protection

Tubing and electrical connectionsQ: rotolock connections, screw terminals

Motor voltage code2: 200-220V/3~/50 Hz & 208-230V/3~/60 Hz4: 380-415V/3~/50 Hz & 460V/3~/60 Hz9: 380V/3~/60 Hz

Other features

Oil sight glass

Oil equalisation

Oil drain

LP gauge port

Gas equalisation

port

9 None Schrader None NoneThreaded

S K 123450903US

Production year

Production week

Manufacturing location Incremental number

A 25BCN 12345678

8 Digits serial number

Month code

Year code

Plant assembly line code

6 FRCC.PC.025.A6.02

Application Guidelines

Page 7: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Technical specifications

Model with activated economizer line

Model without activated economizer line

Volta

ge

Refrigerant Model HPNominal cooling

capacity*Power input* Efficiency* Swept

Volume Displacement Oil Charge Net Weight (with oil)

W Btu/h W COPW/W

EERBtu/h/W cm3/rev m3/h Litres kg

50Hz R404A**

LLZ013 4 4044 13802 3011 1.34 4.57 67.4 11.7 1.62 42

LLZ015 5 4840 16519 3511 1.38 4.71 83.5 14.5 1.62 42

LLZ018 6 5766 19679 4041 1.43 4.88 97.6 17 1.62 43

LLZ024 8 7242 24717 4994 1.45 4.95 120.2 20.9 2.51 46

LLZ034 10 9907 33812 6597 1.50 5.12 168.7 29.4 2.51 51

60Hz R404A**

LLZ013 4 4863 16597 3482 1.40 4.78 67.4 14.2 1.62 42

LLZ015 5 5778 19720 4158 1.39 4.74 83.5 17.5 1.62 42

LLZ018 6 6905 23567 4739 1.46 4.98 97.6 20.5 1.62 43

LLZ024 8 8555 29198 5784 1.48 5.05 120.2 25.3 2.51 46

LLZ034 10 12041 41096 7807 1.54 5.26 168.7 35.4 2.51 51

* Condition: T0:-35°C, Tc: 40°C, SH: 10K SC: 5K Economizer SH: 5K, Economizer ΔT: 5KMotor voltage code 4: 400V/3~/50Hz & 460V/3~/60Hz**R507 performance data are nearly identical to R404A performance data Note: LLZ034 data is preliminary

Volta

ge

Refrigerant Model HPNominal cooling

capacity*Power input* Efficiency* Swept

Volume Displacement Oil Charge Net Weight (with oil)

W Btu/h W COPW/W

EERBtu/h/W cm3/rev m3/h Litres kg

50Hz R404A**

LLZ013 4 2417 8249 2366 1.02 3.48 67.4 11.7 1.62 42

LLZ015 5 2937 10024 2776 1.06 3.62 83.5 14.5 1.62 42

LLZ018 6 3453 11785 3150 1.10 3.75 97.6 17 1.62 43

LLZ024 8 4411 15055 3957 1.11 3.79 120.2 20.9 2.51 46

LLZ034 10 6051 20652 5458 1.11 3.79 168.7 29.4 2.51 51

60Hz R404A**

LLZ013 4 2896 9884 2774 1.04 3.55 67.4 14.2 1.62 42

LLZ015 5 3552 12123 3307 1.07 3.65 83.5 17.5 1.62 42

LLZ018 6 4228 14430 3799 1.11 3.79 97.6 20.5 1.62 43

LLZ024 8 5278 18014 4611 1.14 3.89 120.2 25.3 2.51 46

LLZ034 10 7404 25270 6157 1.20 4.10 168.7 35.4 2.51 51

* Condition: T0: -35°C, Tc: 40°C, SH: 10K, SC: 0K Motor voltage code 4: 400V/3~/50Hz & 460V/3~/60Hz**R507 performance data are nearly identical to R404A performance data Note: LLZ034 data is preliminary

7FRCC.PC.025.A6.02

Application Guidelines

Page 8: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Technical specifications

Model with activated economizer line

Model without activated economizer line

Volta

ge

Refrigerant Model HPNominal cooling

capacity*Power input* Efficiency* Swept

Volume Displacement Oil Charge Net Weight (with oil)

W Btu/h W COPW/W

EERBtu/h/W cm3/rev m3/h Litres kg

50Hz R404A**

LLZ013 4 4819 16447 3087 1.56 5.32 67.4 11.7 1.62 42

LLZ015 5 5713 19498 3595 1.59 5.43 83.5 14.5 1.62 42

LLZ018 6 6806 23229 4137 1.64 5.60 97.6 17 1.62 43

LLZ024 8 8548 29174 5113 1.67 5.70 120.2 20.9 2.51 46

LLZ034 10 11624 39672 6805 1.71 5.84 168.7 29.4 2.51 51

60Hz R404A**

LLZ013 4 5776 19713 3573 1.62 5.53 67.4 14.2 1.62 42

LLZ015 5 6821 23280 4266 1.60 5.46 83.5 17.5 1.62 42

LLZ018 6 8152 27823 4861 1.68 5.73 97.6 20.5 1.62 43

LLZ024 8 10100 34471 5934 1.70 5.80 120.2 25.3 2.51 46

LLZ034 10 14028 47877 8055 1.74 5.94 168.7 35.4 2.51 51

* ARI Condition: T0:-31.7°C, Tc: 40.6°C, RGT: 18.3°C, SC: 5K Economizer SH: 5K, EconomizerΔT: 5KMotor voltage code 4: 400V/3~/50Hz & 460V/3~/60Hz**R507 performance data are nearly identical to R404A performance data Note: LLZ034 data is preliminary

Volta

ge

Refrigerant Model HPNominal cooling

capacity*Power input* Efficiency* Swept

Volume Displacement Oil Charge Net Weight (with oil)

W Btu/h W COPW/W

EERBtu/h/W cm3/rev m3/h Litres kg

50Hz R404A**

LLZ013 4 3213 10966 2507 1.28 4.37 67.4 11.7 1.62 42

LLZ015 5 3898 13304 2949 1.32 4.51 83.5 14.5 1.62 42

LLZ018 6 4583 15642 3346 1.37 4.68 97.6 17 1.62 43

LLZ024 8 5854 19980 4204 1.39 4.74 120.2 20.9 2.51 46

LLZ034 10 7991 27273 5772 1.38 4.71 168.7 29.4 2.51 51

60Hz R404A**

LLZ013 4 3857 13164 2938 1.31 4.47 67.4 14.2 1.62 42

LLZ015 5 4718 16102 3507 1.35 4.61 83.5 17.5 1.62 42

LLZ018 6 5616 19167 4028 1.39 4.74 97.6 20.5 1.62 43

LLZ024 8 7011 23928 4889 1.43 4.88 120.2 25.3 2.51 46

LLZ034 10 9791 33416 6616 1.48 5.05 168.7 35.4 2.51 51

* ARI Condition: T0: -31.7°C, Tc: 40.6°C, RGT: 18.3°C, SC: 0K Motor voltage code 4: 400V/3~/50Hz & 460V/3~/60Hz**R507 performance data are nearly identical to R404A performance data Note: LLZ034 data is preliminary

8 FRCC.PC.025.A6.02

Application Guidelines

Page 9: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Technical specifications

Model with activated economizer line R404A/R507

Model with activated economizer line R404A/R507

ModelTe -40 -35 -30 -25 -20 -15 -10

Tc Cooling (W)

Pe (kW)

Cooling (W)

Pe (kW)

Cooling (W)

Pe (kW)

Cooling (W)

Pe (kW)

Cooling (W)

Pe (kW)

Cooling (W)

Pe (kW)

Cooling (W)

Pe (kW)

50H

z

LLZ013T4 - Eco

30 3400 2.36 4200 2.52 5200 2.66 6300 2.80 7500 2.93 8800 3.05 10100 3.1640 3200 2.85 4000 3.01 5000 3.16 6000 3.30 7100 3.43 8200 3.55 9500 3.6650 - - 3800 3.61 4700 3.80 5600 3.98 6700 4.14 7800 4.30 8900 4.44

LLZ015T4 - Eco

30 4100 2.80 5000 2.95 6100 3.10 7400 3.25 8800 3.38 10500 3.48 12300 3.5340 3900 3.34 4800 3.51 5900 3.70 7100 3.89 8400 4.06 9900 4.20 11700 4.3050 - - 4600 4.24 5600 4.47 6700 4.71 7900 4.94 9300 5.13 10900 5.29

LLZ018T4 - Eco

30 4900 3.23 6000 3.39 7300 3.57 8800 3.74 10500 3.89 12500 4.01 14700 4.0640 4700 3.84 5800 4.04 7000 4.26 8400 4.47 10000 4.67 11800 4.83 13900 4.9450 - - 5500 4.87 6700 5.15 8000 5.42 9400 5.68 11100 5.91 13000 6.09

LLZ024T4 - Eco

30 6200 3.99 7600 4.19 9200 4.41 11100 4.62 13200 4.81 15700 4.95 18500 5.0240 5900 4.75 7200 4.99 8800 5.26 10600 5.53 12600 5.77 14900 5.97 17400 6.1150 - - 6900 6.02 8400 6.36 10000 6.70 11900 7.02 13900 7.30 16300 7.53

LLZ034T4 - Eco

30 8700 5.19 10500 5.47 12700 5.75 15200 6.01 18100 6.23 21400 6.39 25100 6.4840 8200 6.21 9900 6.60 11900 6.97 14200 7.31 16900 7.59 19900 7.81 23200 7.9350 - - 9300 7.99 11100 8.57 13200 9.09 15500 9.53 18200 9.89 21200 10.15

60H

z

LLZ013T4 - Eco

30 4000 2.72 5100 2.90 6200 3.06 7400 3.21 8800 3.35 10400 3.47 12100 3.5740 3800 3.29 4900 3.48 5900 3.66 7100 3.82 8300 3.97 9700 4.10 11300 4.2150 - - 4700 4.18 5600 4.42 6700 4.64 7800 4.85 9100 5.04 10600 5.21

LLZ015T4 - Eco

30 5000 3.30 6000 3.52 7300 3.71 8900 3.87 10600 4.02 12700 4.15 14900 4.2940 4700 3.91 5800 4.16 7000 4.39 8500 4.60 10100 4.81 12000 5.02 14000 5.2450 - - 5600 4.99 6700 5.28 8100 5.56 9600 5.84 11200 6.13 13100 6.43

LLZ018T4 - Eco

30 6000 3.76 7200 4.01 8800 4.22 10600 4.41 12700 4.58 15100 4.73 17800 4.8840 5700 4.45 6900 4.74 8400 5.00 10100 5.25 12100 5.49 14300 5.72 16800 5.9750 - - 6600 5.69 8000 6.02 9700 6.33 11500 6.65 13400 6.98 15600 7.33

LLZ024T4 - Eco

30 7400 4.59 8900 4.89 10800 5.15 13100 5.38 15800 5.59 18700 5.78 22000 5.9640 7000 5.44 8600 5.78 10400 6.10 12600 6.40 15000 6.70 17800 6.98 20800 7.2850 - - 8200 6.95 10000 7.34 12000 7.73 14200 8.12 16600 8.53 19300 8.95

LLZ034T4 - Eco

30 10500 6.18 12900 6.59 15400 6.92 18200 7.19 21500 7.44 25600 7.71 30600 8.0240 9800 7.25 12000 7.81 14300 8.26 16800 8.63 19700 8.97 23400 9.30 27900 9.6550 - - 11100 9.37 13100 10.04 15400 10.62 18000 11.13 21300 11.62 25400 12.10

Condition:Te: Evaporating temperature in °C Tc: Condensing temperature in °C Qo: Cooling Capacity in WSubcooling = 5K Superheat = 10K Pe: Power input in kWEconomizer SH: 5K, Economizer ΔT: 5KNote: LLZ034 data is preliminary

ModelTe -40 -35 -30 -25 -20 -15 -10

Tc Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

50H

z

LLZ013T4 - Eco

30 3500 2.31 4400 2.48 5400 2.64 6500 2.78 7700 2.92 9000 3.05 10400 3.1740 3400 2.77 4200 2.95 5200 3.11 6200 3.27 7300 3.41 8500 3.54 9800 3.6650 - - 4000 3.50 4900 3.71 5900 3.91 7000 4.09 8100 4.27 9300 4.43

LLZ015T4 - Eco

30 4200 2.73 5200 2.89 6300 3.06 7600 3.23 9100 3.37 10800 3.48 12600 3.5440 4100 3.23 5000 3.42 6100 3.63 7300 3.84 8700 4.03 10300 4.19 12000 4.2950 - - 4800 4.10 5900 4.36 7000 4.62 8300 4.87 9700 5.10 11300 5.27

LLZ018T4 - Eco

30 5000 3.14 6200 3.33 7500 3.53 9100 3.72 10800 3.88 12800 4.01 15000 4.0740 4800 3.72 6000 3.94 7300 4.18 8700 4.42 10400 4.64 12200 4.82 14300 4.9450 - - 5800 4.72 7000 5.02 8400 5.32 9900 5.61 11600 5.86 13400 6.07

LLZ024T4 - Eco

30 6300 3.88 7800 4.11 9500 4.36 11400 4.59 13600 4.80 16100 4.95 18900 5.0340 6100 4.59 7500 4.87 9100 5.16 11000 5.46 13000 5.73 15400 5.95 17900 6.1150 - - 7200 5.83 8800 6.20 10500 6.58 12400 6.93 14500 7.25 16900 7.50

LLZ034T4 - Eco

30 9000 5.08 10900 5.39 13100 5.69 15700 5.97 18600 6.21 21900 6.38 25600 6.4940 8500 6.02 10300 6.45 12400 6.86 14800 7.23 17500 7.53 20500 7.77 23900 7.9150 - - 9700 7.76 11600 8.37 13800 8.92 16200 9.41 18900 9.80 21900 10.09

60H

z

LLZ013T4 - Eco

30 4100 2.66 5200 2.85 6400 3.03 7700 3.19 9100 3.34 10600 3.47 12400 3.5840 4000 3.19 5100 3.40 6200 3.60 7400 3.78 8600 3.94 10100 4.08 11700 4.2150 - - 4900 4.06 5900 4.32 7000 4.56 8200 4.79 9500 5.00 10900 5.19

LLZ015T4 - Eco

30 5100 3.22 6200 3.45 7600 3.66 9100 3.84 11000 4.01 13000 4.15 15200 4.3040 4900 3.78 6000 4.05 7300 4.31 8800 4.55 10500 4.78 12400 5.00 14400 5.2350 - - 5800 4.84 7100 5.15 8500 5.46 10000 5.77 11700 6.08 13500 6.41

LLZ018T4 - Eco

30 6100 3.67 7400 3.94 9000 4.17 10900 4.38 13100 4.56 15500 4.73 18200 4.9040 5900 4.31 7200 4.62 8700 4.91 10500 5.18 12600 5.44 14800 5.70 17200 5.9650 - - 7000 5.51 8400 5.87 10100 6.22 12000 6.57 14000 6.93 16200 7.30

LLZ024T4 - Eco

30 7600 4.48 9200 4.80 11200 5.09 13500 5.34 16200 5.57 19200 5.78 22500 5.9840 7300 5.26 8900 5.64 10800 5.99 13100 6.33 15600 6.65 18400 6.96 21400 7.2850 - - 8600 6.73 10500 7.16 12500 7.59 14800 8.02 17300 8.46 20000 8.91

LLZ034T4 - Eco

30 10800 6.04 13400 6.49 15900 6.85 18800 7.14 22100 7.42 26200 7.70 31300 8.0340 10100 7.04 12500 7.64 14900 8.13 17500 8.53 20400 8.90 24100 9.25 28700 9.6350 - - 11600 9.09 13800 9.81 16100 10.43 18800 10.98 22100 11.51 26300 12.04

Condition:Te: Evaporating temperature in °C Tc: Condensing temperature in °C Qo: Cooling Capacity in WReturn gas temperature = 18.3°C Subcooling = 5K Pe: Power input in kWEconomizer SH: 5K, Economizer ΔT: 5KNote: LLZ034 data is preliminary

9FRCC.PC.025.A6.02

Application Guidelines

Page 10: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Technical specifications

Model without activated economizer line R404A/R507

Model without activated economizer line R404A/R507

ModelTe -40 -35 -30 -25 -20 -15 -10

Tc Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

50H

z

LLZ013T430 2200 1.94 2900 2.10 3700 2.25 4600 2.40 5700 2.53 6900 2.62 8400 2.6640 1800 2.19 2400 2.37 3100 2.55 3900 2.74 4800 2.91 6000 3.06 7300 3.1750 - - 1900 2.72 2500 2.92 3200 3.14 3900 3.35 4900 3.55 6000 3.73

LLZ015T430 2700 2.28 3500 2.48 4400 2.69 5600 2.89 7000 3.08 8600 3.25 10600 3.3840 2300 2.57 2900 2.78 3800 3.01 4700 3.26 5900 3.50 7400 3.74 9000 3.9650 - - 2300 3.16 3000 3.41 3800 3.69 4800 3.98 6000 4.28 7400 4.58

LLZ018T430 3200 2.59 4100 2.81 5200 3.05 6600 3.28 8200 3.50 10200 3.69 12400 3.8340 2700 2.91 3500 3.15 4400 3.42 5600 3.69 7000 3.98 8600 4.24 10600 4.4950 - - 2800 3.58 3500 3.87 4500 4.18 5600 4.52 7000 4.86 8700 5.19

LLZ024T430 4100 3.25 5200 3.54 6700 3.83 8400 4.12 10500 4.40 13000 4.63 15900 4.8140 3400 3.66 4400 3.96 5600 4.29 7100 4.64 8900 5.00 11000 5.33 13600 5.6450 - - 3500 4.50 4500 4.86 5700 5.25 7200 5.68 9000 6.10 11100 6.52

LLZ034T430 5700 4.29 7200 4.66 9100 5.05 11500 5.44 14300 5.80 17600 6.11 21500 6.3340 4700 5.12 6100 5.46 7700 5.85 9600 6.27 12000 6.68 14800 7.08 18200 7.4250 - - 4800 6.80 6100 7.13 7700 7.52 9600 7.94 11900 8.37 14700 8.77

60H

z

LLZ013T430 2600 2.27 3400 2.46 4400 2.65 5500 2.81 6800 2.94 8300 3.03 10100 3.0640 2200 2.57 2900 2.77 3700 2.99 4700 3.20 5800 3.39 7100 3.56 8600 3.6950 - - 2300 3.15 3000 3.39 3800 3.63 4700 3.88 5800 4.11 7100 4.32

LLZ015T430 3300 2.74 4200 2.98 5300 3.22 6700 3.46 8400 3.68 10400 3.85 12800 3.9640 2700 3.07 3600 3.31 4500 3.58 5700 3.86 7200 4.15 8900 4.41 10900 4.6350 - - 2900 3.76 3700 4.03 4700 4.34 5900 4.67 7300 5.00 9000 5.31

LLZ018T430 3900 3.15 5000 3.42 6400 3.70 8000 3.98 10000 4.23 12400 4.42 15200 4.5540 3300 3.53 4200 3.80 5400 4.11 6800 4.44 8600 4.77 10600 5.07 13000 5.3250 - - 3400 4.32 4400 4.63 5600 4.99 7000 5.36 8700 5.74 10700 6.10

LLZ024T430 4800 3.82 6200 4.15 7900 4.49 10000 4.83 12500 5.13 15500 5.37 19000 5.5340 4100 4.28 5300 4.61 6800 4.99 8500 5.39 10700 5.78 13200 6.15 16300 6.4650 - - 4200 5.24 5500 5.62 6900 6.05 8700 6.51 10900 6.97 13400 7.41

LLZ034T430 6900 4.86 8800 5.43 11100 5.98 13900 6.48 17200 6.92 21100 7.29 25600 7.5840 5700 5.52 7400 6.16 9400 6.77 11800 7.34 14700 7.86 18100 8.31 22100 8.6750 - - 5900 7.09 7600 7.77 9600 8.42 12000 9.02 14800 9.56 18200 10.02

Condition:Te: Evaporating temperature in °C Tc: Condensing temperature in °C Qo: Cooling Capacity in WSubcooling = 0K Superheat = 10K Pe: Power input in kWNote: LLZ034 data is preliminary

ModelTe -40 -35 -30 -25 -20 -15 -10

Tc Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

Cooling(W)

Pe(kW)

50H

z

LLZ013T430 2500 1.94 3200 2.10 4000 2.25 4900 2.40 6000 2.53 7300 2.62 8700 2.6640 - - - - 3500 2.55 4300 2.74 5300 2.91 6400 3.06 7600 3.1750 - - - - - - - - 4500 3.35 5400 3.55 6500 3.73

LLZ015T430 3000 2.28 3800 2.48 4800 2.69 6000 2.89 7400 3.08 9100 3.25 11000 3.3840 - - - - 4200 3.01 5300 3.26 6500 3.50 7900 3.74 9500 3.9650 - - - - - - - - 5400 3.98 6600 4.28 8000 4.58

LLZ018T430 3600 2.59 4500 2.81 5700 3.05 7100 3.28 8700 3.50 10600 3.69 12900 3.8340 - - - - 5000 3.42 6200 3.69 7600 3.98 9300 4.24 11200 4.4950 - - - - - - - - 6400 4.52 7800 4.86 9400 5.19

LLZ024T430 4600 3.25 5800 3.54 7300 3.83 9000 4.12 11100 4.40 13600 4.63 16400 4.8140 - - - - 6400 4.29 7900 4.64 9700 5.00 11800 5.33 14300 5.6450 - - - - - - - - 8200 5.68 9900 6.10 12000 6.52

LLZ034T430 6300 4.29 8000 4.66 9900 5.05 12300 5.44 15100 5.80 18400 6.11 22300 6.3340 - - - - 8700 5.85 10700 6.27 13100 6.68 15900 7.08 19100 7.4250 - - - - - - - - 10900 7.94 13200 8.37 15800 8.77

60H

z

LLZ013T430 2900 2.27 3800 2.46 4700 2.65 5900 2.81 7200 2.94 8700 3.03 10400 3.0640 - - - - 4200 2.99 5200 3.20 6300 3.39 7600 3.56 9100 3.6950 - - - - - - - - 5400 3.88 6400 4.11 7700 4.32

LLZ015T430 3600 2.74 4600 2.98 5800 3.22 7200 3.46 8900 3.68 10900 3.85 13200 3.9640 - - - - 5100 3.58 6400 3.86 7800 4.15 9500 4.41 11500 4.6350 - - - - - - - - 6700 4.67 8100 5.00 9700 5.31

LLZ018T430 4300 3.15 5500 3.42 6900 3.70 8600 3.98 10600 4.23 13000 4.42 15700 4.5540 - - - - 6100 4.11 7600 4.44 9300 4.77 11400 5.07 13700 5.3250 - - - - - - - - 7900 5.36 9600 5.74 11600 6.10

LLZ024T430 5400 3.82 6900 4.15 8600 4.49 10800 4.83 13300 5.13 16200 5.37 19600 5.5340 - - - - 7600 4.99 9500 5.39 11600 5.78 14200 6.15 17100 6.4650 - - - - - - - - 9900 6.51 12000 6.97 14500 7.41

LLZ034T430 7700 4.86 9700 5.43 12100 5.98 14900 6.48 18200 6.92 22100 7.29 26500 7.5840 - - - - 10600 6.77 13100 7.34 16000 7.86 19400 8.31 23300 8.6750 - - - - - - - - 13600 9.02 16400 9.56 19700 10.02

Condition:Te: Evaporating temperature in °C Tc: Condensing temperature in °C Qo: Cooling Capacity in WReturn gas temperature = 18.3°C Subcooling = 0K Pe: Power input in kWNote: LLZ034 data is preliminary

10 FRCC.PC.025.A6.02

Application Guidelines

Page 11: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Dimensions

LLZ013-015-018

Mounting grommetTerminal box

Refer to section “Ordering information and packaging” for overview of shipped mounting accessories

Ring connect screw terminalsC terminal box type

CT₁

ST₂

RT₃

Ø 41

29.5

Recommended torque for mounting bolts: 11 Nm (±1 Nm)

Ø11

108.8Schrader

119.3

78.5 - 80.5 34° 31°45°±2°

1°95.3

124.9suction

line106.4sightglass

190.25 - 190.75

231.9

Discharge lineØ1.00" - 14UN (2A)

92 - 94

451

238.4

Sight glass

86.4

7.2

302.2

374.5

478.2

Suction lineØ1.25" - 12UN (2A)

Economizer lineØ1.00" - 14UN (2A)

Schrader valveand cover

231.9

190.25 - 190.75

95.3

133

11FRCC.PC.025.A6.02

Application Guidelines

Page 12: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Dimensions

LLZ024

Mounting grommetTerminal box

Refer to section “Ordering information and packaging” for overview of shipped mounting accessories

Ring connect screw terminalsC terminal box type

CT₁

ST₂

RT₃

Ø 41

29.5

Recommended torque for mounting bolts: 11 Nm (±1 Nm)

Ø11

231.9

108.8

95.25

13395.25

190.25-190.75

231.9

119.3

34° 31° 73°

14°±2°

45°±2°

106.4sight glass

124.9suction

line

78.5-80.5

Discharge lineØ1.25" - 12UN (2A)19.24-19.12 I.D.

92.0-94.0

Sight glass 532.7

Schrader valveand cover

414.5

342.2

126.47.2

48.4

505.5

278.4

Suction lineØ1.75" - 12UN (2A)28.83-25.65 I.D.

Economizer lineØ1.00" - 14UN (2A)12.90-12.70 I.D.

4x Ø19.0 - 20.0

Ø183.14-185.14

190.25-190.75

12 FRCC.PC.025.A6.02

Application Guidelines

Page 13: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Dimensions

LLZ034

Mounting grommetTerminal box

Refer to section “Ordering information and packaging” for overview of shipped mounting accessoriesNote: LLZ034 drawing is preliminary

Ring connect screw terminalsC terminal box type

CT₁

ST₂

RT₃

Economizer lineØ1.00" - 14UN (2A)

Suction lineØ1.75" - 12UN (2A)

Sight glass

7.2

557.7

367.2

439.5

126.4

48.4

Discharge lineØ1.25" - 14UN (2A)

92 - 94

530.5

303.4

183.14 - 185.14

Schrader valveand cover

45°±2°31°

73°34°

78.5 - 80.5

119.3

133

231.9190.25 - 190.75

95.25108.8

Schrader

190.25 - 190.75

231.9

124.9suction

line106.4sightglass

14°±2°

95.25

4x Ø19 - 20

Ø 41

29.5

Recommended torque for mounting bolts: 11 Nm (±1 Nm)

Ø11

13FRCC.PC.025.A6.02

Application Guidelines

Page 14: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Dimensions

LLZ scroll compressors are factory delivered with rotolock connections only.

Oil sight glass

Suction and discharge connections

LLZ scroll compressors come equipped with a threaded oil sight glass with 1”1/8 - 18 UNEF connection. It can be used for a visual check of the oil amount and condition or it may be replaced by an accessory oil management device. The oil level must be visible in the sight glass during operation.

The oil fill and drain connection and gauge port is a 1/4" male flare connector incorporating a schrader valve.

Schrader

Oil sight glass

Schrader valveand cap

Compressor ModelsRotolock Sizes

Suction Fitting (in) Discharge Fitting (in) Econo Fitting (in)

LZL013 1”1/4 1" 1"

LLZ015 1”1/4 1" 1"

LLZ018 1”1/4 1" 1"

LLZ024 1”3/4 1”1/4 1"

LLZ034 1”3/4 1”1/4 1"

Note: LLZ034 data is preliminary

14 FRCC.PC.025.A6.02

Application Guidelines

Page 15: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Electrical data, connections and wiring

LLZ scroll compressors are available in 3 different motor voltages.Motor voltage

The compressor terminal box IP rating according to CEI 529 is IP22 for all models.• First numeral, level of protection against contact and foreign objects

2 protection against object size over 12.5 mm (fingers or similar)• Second numeral, level of protection against water

2 protection against dripping water when tilted up to 15°The IP rating can be upgraded to IP54 with an accessory kit (see section “Spare parts and accessories”).

IP rating

LLZ scroll compressors will only compress gas while rotating counter-clockwise (when viewed from the compressor top). Three-phase motors will start and run in either direction, depending on the phase angles of the supplied power. Care must be taken during installation to ensure that the compressor operates in the correct direction (see “Phase sequence and reverse rotation protection”).

The drawings hereafter show electrical terminal labelling and should be used as a reference when wiring the compressor. For three phase applications, the terminals are labelled T1, T2, and T3.

The terminal cover and gasket should be installed prior to operation of the compressor. Respect the "up" marking on gasket and cover and ensure

that the two outside tabs of the cover engage the terminal box.

Wiring connections

Terminal cover mounting

Terminal cover removal

Ring connect screw terminalsC terminal box type

T1

T2

T3

push

push

push

Motor voltage code 2

Motor voltage code 4

Motor voltage code 9

Nominal voltage 50 Hz 200-220 V - 3 ph 380-415 V - 3 ph -

Voltage range 50 Hz 180 - 242 V 342 - 456 V -

Nominal voltage 60 Hz 208-230 V - 3 ph 460 V - 3 ph 380 V - 3 ph

Voltage range 60 Hz 187 - 253 V 414 - 506 V 342 - 418 V

15FRCC.PC.025.A6.02

Application Guidelines

Page 16: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Electrical data, connections and wiring

Three phase electrical characteristics

Winding resistance Winding resistance is the resistance between indicated terminal pins at 25°C (resistance value +/- 7%).Winding resistance is generally low and it requires adapted tools for precise measurement. Use a digital ohm-meter, a ‘4 wires’ method and measure under stabilised ambient temperature. Winding resistance varies strongly with winding temperature. If the compressor is stabilised at a different value than 25°C, the measured resistance must be corrected using the following formula:

a + tamb

Rtamb = R25°C _________ a + t25°C

t25°C: reference temperature = 25°Ctamb: temperature during measurement (°C)R25°C: winding resistance at 25°CRamb: winding resistance at tamb

coefficient a = 234.5

LRA is the higher average current as measured on a mechanically blocked compressor tested under nominal voltage. LRA is printed on the nameplate.

The LRA value can be used as a rough estimation for the starting current. However in most cases, the real starting current will be lower. Many countries have defined limits for the starting current in domestic use. A soft starter can be applied to reduce starting current.

The MCC is the current at which the internal motor protection trips under maximum load and low voltage conditions.

This MCC value is the maximum at which the compressor can be operated in transient conditions and out of the application envelope. Above this value the overload will switch off to protect the motor.

MCC (Maximum Continuous Current)

LRA (Locked Rotor Amp)

The Max Oper. A is the current when the compressor operates at maximum load conditions and 10% below nominal voltage.

This value, which is the max rated load current for the compressor, is new on the nameplate.

Max Oper. A can be used to select cables and contactors.

In normal operation, the compressor current consumption is always less than the Max Oper. A value.

Max Oper. A (Maximum Operating Amp)

ModelLRA RLA MCC

assigned MOC Winding Resistances (Ohm)

A A A Economized cycle

Standard cycle T1-T3 T1-T2 T2-T3

Mot

or v

olta

ge c

ode

438

0-41

5 V

/ 3 p

h / 5

0 H

z.46

0 V

/ 3 p

h / 6

0 H

z LLZ013T4 62.0 8.0 12.0 9.8 8.0 2.30 2.30 2.40

LLZ015T4 88.5 9.6 15.0 12.0 9.8 1.69 1.69 1.69

LLZ018T4 90.0 10.0 15.0 14.4 11.8 1.61 1.70 1.66

LLZ024T4 95.0 13.5 21.0 18.3 15.0 1.48 1.48 1.48

LLZ034T4 150.0 16.7 26.0 22.7 19.1 0.84 0.84 0.84

Mot

or v

olta

ge c

ode

220

0-22

0 V

/ 3ph

/ 50

Hz.

20

8-23

0 V

/ 3 p

h / 6

0 H

z

LLZ013T2 123.0 17.9 25.0 20.0 16.4 0.60 0.60 0.61

LLZ015T2 180.0 18.5 29.0 23.0 18.9 0.50 0.50 0.50

LLZ018T2 184.0 20.0 31.0 29.4 24.1 0.43 0.43 0.44

LLZ024T2 190.0 25.6 40.0 34.7 28.4 0.37 0.37 0.37

LLZ034T2 N/A N/A N/A N/A N/A N/A N/A N/A

Mot

or v

olta

ge c

ode

938

0 V

/ 3ph

/ 60

Hz.

LLZ013T9 81 9.0 14.0 11.8 9.4 1.49 1.46 1.48

LLZ015T9 81 10.9 17.0 14.2 11.3 1.49 1.46 1.48

LLZ018T9 106 12.8 20.0 16.5 13.7 1.13 1.09 1.10

LLZ024T9 135 13.5 21.0 19.4 17.1 0.93 0.91 0.93

LLZ034T9 155 19.0 29.6 25.5 22.9 0.63 0.63 0.63

Note: LLZ034 data is preliminary

16 FRCC.PC.025.A6.02

Application Guidelines

Page 17: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Electrical data, connections and wiring

Electrical wiring diagram Suggested wiring diagram with "one shot" pump down cycle and safety lock-out relay

Control device ............................................THOptional short cycle timer (3 mins) 180 sControl relay ................................................KALiquid Line Solenoid valve .................LLSVCompressor contactor ............................ KMPhase monitor ........................................... PMSafety lock out relay ..................................KSPump-down control low pressure switch ...........................................LPHigh pressure safety switch ................. HPsFused disconnect ......................................Q1Fuses ...............................................................F1Compressor motor ......................................MDischarge gas thermostat ...................DGT

Internal motor protection LLZ scroll compressors are equipped with an internal line break protector mounted on the motor windings. The protector is an automatic reset device, containing a snap action bimetal switch.

Internal protectors respond to over-current and overheating. They are designed to interrupt

motor current under a variety of fault conditions, such as failure to start, running overload and fan failure.

If the internal overload protector trips out, it must cool down to about 60°C to reset. Depending on ambient temperature, this may take up to several hours.

The compressor will only operate properly in a single direction. Use a phase meter to establish the phase orders and connect line phases L1, L2 and L3 to terminals T1, T2 and T3, respectively. Please note LLZ compressors are forbidden to do reverse rotation.

A service technician should be present at initial start-up to verify that supply power is properly phased and that the compressor and auxiliaries are rotating in the correct direction.

For LLZ phase monitors are mandatory. The selected phase monitor should lock out the compressor from operation in reverse.

Phase sequence and reverse rotation protection

For three-phase applications the voltage measured at the compressor terminals for each

phase should be within ± 2% of the average for all phases.

Voltage imbalance

MDGT

HPs180 s

THLP

CONTROL CIRCUIT

F1F1

KM

KM

KM

KA KA

A1

A2

A3

KA

KA

KS

KS

KS

L1 L3 L2

Q1

T1

T3

T2

LLSV KS

Wiring diagram with pump-down cycle

PM

17FRCC.PC.025.A6.02

Application Guidelines

Page 18: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Approvals and certifications

LLZ scroll compressors comply with the following approvals and certificates.

Certificates are listed on the product datasheets: http://www.danfoss.com/odsg

Approvals and certificates

Conformity to directives

Internal free volume

CE 0062 or CE 0038 (European Directive) All LLZ models

UL (Underwriters Laboratories) All LLZ models

CCC LLZ013-015-018 code 4

Other approvals/certificates Contact Danfoss

Products Internal free volume at LP side without oil (litre)

LLZ013-015-018 4.74LLZ024-034 5.95

Note: LLZ034 data is preliminary

Products LLZ013 to 034

Refrigerating fluids Group 2Category PED IEvaluation module no scopeService temperature - Ts -40°C < Ts < 55°cLLZ - Service pressure - Ps 25.44 bar(g)Declaration of conformity contact DanfossMarking of conformity CE

Pressure equipment directive 97/23/ECMachinery directive 98/35/EC annex II b

Low voltage directive 2006/95ECElectromagnetic compatibility 2004/108/CE

18 FRCC.PC.025.A6.02

Application Guidelines

Page 19: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Operating conditions

The scroll compressor application range is influenced by several parameters which need to be monitored for a safe and reliable operation.These parameters and the main recommendations for good practice and safety devices are explained hereunder.

• Refrigerant and lubricants• Motor supply• Compressor ambient temperature• Application envelope (evaporating

temperature, condensing temperature, return gas temperature)

General information

Refrigerant and lubricants

When choosing a refrigerant, different aspects must be taken into consideration:• Legislation (now and in the future)• Safety• Application envelope in relation to expected

running conditions• Compressor capacity and efficiency• Compressor manufacturer recommendations

and guidelines

Additional points could influence the final choice:• Environmental considerations• Standardisation of refrigerants and lubricants• Refrigerant cost• Refrigerant availability

R404A

R507

PVE

R404A is an HFC refrigerant. R404A has zero ozone depletion potential (ODP = 0). R404A is especially suitable for low evaporating temperature applications but it can also be applied to medium evaporating temperature applications. R404A is a mixture and has a very

small temperature glide, and therefore must be charged in its liquid phase, but for most other aspects this small glide can be neglected. Because of the small glide, R404A is often called a near-azeotropic mixture.

R507 is an HFC refrigerant with properties comparable to R404A. R507 has no ozone depletion potential (ODP = 0). As with R404A, R507 is particularly suitable for low evaporating

temperature applications but it can also be used for medium evaporating temperature applications. R507 is an azeotropic mixture with no temperature glide.

Polyvinyl ether (PVE) is an innovative refrigeration lubricant for HFC refrigerant systems. PVE is as hygroscopic as existing polyolester lubricants (POE), but PVE doesn’t chemically react with water; no acids are formed and compressor evacuation is easier.

The compressor technology applied in LLZ scroll compressors in combination with PVE lubricant provides the best possible result in terms of reliability and compressor lifetime.

Motor supply LLZ scroll compressors can be operated at nominal voltages as indicated in table section “Motor voltage”. Under-voltage and over-voltage

operation is allowed within the indicated voltage ranges.

LLZ scroll compressors can be applied from -35°C to 50°C ambient temperature. The compressors are designed as 100% suction gas

cooled without need for additional fan cooling. Ambient temperature has very little effect on the compressor performance.

In case of enclosed fitting and high ambient temperature it is recommend to check the temperature of power recommended wires and conformity to their insulation specification.

In case of safe tripping by the internal compressor overload protection the compressor must cool down to about 60°C before the overload will reset. A high ambient temperature can strongly delay this cool-down process.

Compressor ambient temperature

High ambient temperature

Although the compressor itself can withstand low ambient temperature, the system may require specific design features to ensure safe

and reliable operation. See section ‘Specific application recommendations’.

Low ambient temperature

19FRCC.PC.025.A6.02

Application Guidelines

Page 20: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Operating conditions

The operating envelopes for LLZ scroll compressors are given in the figures below, where the condensing and evaporating temperatures represent the range for steady-state operation. Under transient conditions, such as start-up and defrost, the compressor may operate outside this envelope for short periods.

The figures below show the operating envelopes for LLZ scroll compressors with refrigerants

R404A/507. The operating limits serve to define the envelope within which reliable operations of the compressor are guaranteed:• Maximum discharge gas temperature: +135°C• A suction superheat below 5 K is not

recommended due to the risk of liquid flood back

• Minimum and maximum evaporating and condensing temperatures as per the operating envelopes.

Application envelope

With activated economizer line

Without activated economizer line

The difference between the operating envelope with and without the activated economizer line is the suction status. The operating envelope with economizer is based on 18.3°C RGT (return gas temperature) which equals 58.3 K suction superheat at -40°C evaporating temperature. While the operating envelope without

economizer is based on 20 K suction superheat. Consequently, the compressor with activated economizer line can achieve the same envelope with much higher suction superheat. In other words, the economizer can enlarge the envelope based on the same suction superheat.

Satu

rate

d di

scha

rge

tem

pera

ture

(°C)

Saturated suction temperature (°C)

RGT 18.3°C

Low temperature refrigeration operating envelope with economizer (R404A/R507)

-45 -40 -35 -30 -25 -20 -15 -10 -5

5

0

10

15

20

25

30

35

40

45

50

55

60

65

Satu

rate

d di

scha

rge

tem

pera

ture

(°C)

Saturated suction temperature (°C)

20K superheat

Low temperature refrigeration operating envelope without economizer (R404A/R507)

LLZ non-eco with RGT of 18.3°C

-45 -40 -35 -30 -25 -20 -15 -10 -5

5

0

10

15

20

25

30

35

40

45

50

55

60

65

20 FRCC.PC.025.A6.02

Application Guidelines

Page 21: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Operating conditions

Discharge gas temperature protection (DGT)

DGT protection is mandatory, in case high and low pressure switch settings do not protect sufficiently against operation outside the envelop. Please refer to the examples below, which illustrate where DGT protection is required (n°1) and where it is not (n°2).

The compressor must not be allowed to cycle on the discharge gas thermostat. Continuous operations beyond the compressor’s operating range will cause serious damage to the compressor!

A DGT accessory is available from Danfoss: refer to section “Spare parts and accessories”.

The discharge temperature depends mainly on the combination of evaporating temperature, condensing temperature and suction gas superheat. Discharge gas temperature should be controlled with an isolated thermocouple or

thermostat attached to the discharge line 15 cm (6 inches) from the compressor shell. Maximum discharge gas temperature must not exceed 135°C (275°F) when the compressor is running within the approved operating envelope.

Maximum discharge gas temperature

Example 1 (R404A, RGT 18.3°C) LP switch setting: LP1 = 1.02 bar (g) (-30°C) HP switch setting: HP1 = 26.24 bar (g) (58°C) The LP and HP switches do not protect sufficiently against operation outside the envelope. DGT protection is required to avoid operation in the hatched area.

Example 2 (R404A, RGT 18.3°C) LP switch setting: LP2 = 1.47 bar (g) (-25°C) HP switch setting: HP2 = 17.15 bar (g) (40°C) The LP and HP switches protect against operation outside the envelope. No DGT protection required.

Discharge line

Insulation

Bracket

Thermostat

R404A

10

15

20

25

30

35

40

45

50

55

60

65

0

5

-35 -30 -25 -20 -15 -10 -5-45 -40

Saturated suction temperature (°C)

Satu

rate

d di

scha

rge

tem

pera

ture

(°C

)

Low temperature refrigeration operating envelope with economizer (R404A/R507)

Example 1

Example 2

LP1LP2

HP1

HP2

RGT 18.3°C

21FRCC.PC.025.A6.02

Application Guidelines

Page 22: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Operating conditions

A low pressure (LP) safety switch is recommended. LLZ scroll compressors exhibit high volumetric efficiency and may draw very low vacuum levels, which could induce scroll instability and electrical arcing at the internal cluster. The minimum low-pressure safety switch setting is given in the above table. For systems without pump-down, the LP safety switch

must either be a manual lockout device or an automatic switch wired into an electrical lockout circuit. There should be no delay or bypass(not more than 1s) on LP safety switch. The LP switch tolerance must not allow for vacuum operations of the compressor. LP switch settings for pump-down cycles with automatic reset are also listed in the table above.

Low pressure

On/off cycling (cycle rate limit)

Suction pressure protection

Depending on the application, a number higher than 12 starts per hour can reduce the service life of the motor-compressor unit. A one-minute time out is recommended.

The system must be designed in a way that provides a minimum compressor running time

of two minutes so as to provide for sufficient motor cooling after start-up along with proper oil return. Note that the oil return may vary since it depends upon system design.

Danfoss recommends a restart delay timer to limit compressor cycling.

In case of big heat load variation, in order to limit LLZ evaporating temperature space (maximum suction pressure) within -10C, it is recommended

to adopt an expansion valve with MOP (maximum operation pressure) function.

LLZ scroll compressors are not equipped with an internal pressure relief valve; therefore a high pressure switch is required to shut down the compressor should the discharge pressure exceed the values shown in the table above.

The high-pressure switch can be set to lower values depending on the application and

ambient conditions. The HP switch must either be placed in a lockout circuit or consist of a manual reset device to prevent cycling around the high-pressure limit. If a discharge valve is used, the HP switch must be connected to the service valve gauge port, which must not be isolated.

High pressure

R404A/R507

Working pressure range high side bar(g) 5.94~27.74

Working pressure range lower side bar(g) 0.33~3.34

Maximum high pressure safety switch setting bar(g) 29.7

Minimum low pressure safety switch setting bar(g) 0.15

Recommended pump-down switch settings bar(g) 1.5 bar below nominal evaporating pressure

Min low pressure pump-down switch setting bar(g) 0.15

LP safety switch shall never have time delay.

High and low pressure protection

22 FRCC.PC.025.A6.02

Application Guidelines

Page 23: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

System design recommendations

Essential piping design recommendations

Proper piping practices should be employed to ensure adequate oil return, even under minimum load conditions with special consideration given to the size and slope of the tubing coming from the evaporator. Tubing returns from the evaporator should be designed so as not to trap oil and to prevent oil and refrigerant migration back to the compressor during off-cycles.Regarding system safety, U trap and external discharge valve are recommended to prevent liquid migration.

In installations with good oil return and line runs up to 20 m, no additional oil is required. If installation lines exceed 20 m, additional oil may be needed. 2-3% of the total system refrigerant charge (in kg) can be used to roughly define the required oil top-up quantity (in litres) but in any case the oil charge has to be adjusted based on the oil level in the compressor sight glass.

If the evaporator lies above the compressor, the addition of a pump-down cycle is strongly recommended. If a pump-down cycle were to be omitted, the suction line must have a loop at the evaporator outlet to prevent refrigerant from draining into the compressor during off-cycles.

If the evaporator is situated below the compressor, the suction riser must be trapped to ensure the oil return to the compressor (see fig.1).

When the condenser is mounted at a higher position than the compressor, a suitably sized “U”-shaped trap close to the compressor is necessary to prevent oil leaving the compressor from draining back to the discharge side of the compressor during off-cycle. The upper loop also helps avoid condensed liquid refrigerant from draining back to the compressor when stopped (see fig. 2). The maximum elevation difference between the indoor and outdoor section cannot exceed 8 m. System manufacturers should specify precautions for any applications that exceed these limits to ensure compressor reliability.

Economizer heat exchanger piping shall be arranged in a count flow of gas and liquid as below to assure optimum heat transfer and therefore best subcooling effect.

Piping should be designed with adequate three-dimensional flexibility (figure 2). It should not be in contact with the surrounding structure, unless a proper tubing mount has been installed. This protection proves necessary to avoid excess vibration, which can ultimately result in connection or tube failure due to fatigue or wear from abrasion. Aside from tubing and connection damage, excess vibration may be transmitted to the surrounding structure and generate an unacceptable sound level within that structure as well (for more information on sound and vibration, see the section on: “Sound and vibration management”).

General Successful application of scroll compressors is dependent on careful selection of the compressor for the application. If the compressor is not correct for the system, it will operate beyond the limits given in this manual. Poor performance, reduced reliability, or both may result.

It is always recommended to install an oil separator for low temperature and long piping application.

0.5% slope,4 m/s or more

0.5% slope,4 m/s or more

U-trap

U-trap, as short as possible

U-trap, as short as possible

max. 4 m

�g.1

max. 4 m

8 to 12 m/s

To condenser

Evaporator

Condenser

HP

U-trap

3D �exibility

Upper loop

LP

�g. 2

23FRCC.PC.025.A6.02

Application Guidelines

Page 24: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

System design recommendations

Economizer selection The key parameter in determining proper economizer size is Saturated Injection Temperature (Tsi). Tsi is provided by Danfoss selection software and this value has been validated through extensive testing at variable operating conditions. In order to optimize system performance while maintaining system reliability and functionality, the economizer should be sized based on 5 K condenser subcooling, 5K economizer temperature difference and 5K economizer superheat

as indicated in the below chart. Once these parameters are set, the economizer load can be calculated by the below equation.

Economizer load = Evaporating mass flow, m (Enthalpy of liquid entering economizer, h2 - Enthalpy of liquid leaving economizer, h1) = Economizer injection mass flow, i (Enthalpy of vapour leaving economizer, h3 - Enthalpy of vapour entering economizer, h2).

Superheat at economizer outlet, 5K

Economizer temperature difference, 5K

h1

Tlo

Tvi

Tli

Pi

P

h

i

m

m+i

TsiTvo

h2 h3

Condenser Subcooling, 5K

Economizersubcooling

24 FRCC.PC.025.A6.02

Application Guidelines

Page 25: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

System design recommendations

Refrigerant charge limit LLZ scroll compressors can tolerate liquid refrigerant up to a certain extent without major problems. However, excessive liquid refrigerant in the compressor is always unfavourable for service life. Besides, the installation cooling capacity may be reduced because of the evaporation taking place in the compressor and/or the suction line instead of the evaporator. System design must be such that the amount of liquid refrigerant in the compressor is limited. In this respect, follow the

guidelines given in the section “essential piping design recommendations” in priority.Use the tables below to quickly evaluate the required compressor protection in relation with the system charge and the application. When refrigerant is charged over the limit, suction accumulator or liquid receiver is a must. More detailed information can be found in the paragraphs hereafter. Please contact Danfoss for any deviation from these guidelines.

Model Refrigerant charge limit (kg)LLZ013-015-018 4.54

LLZ024-034 7.26

Note: LLZ034 data is preliminary

Off-cycle migration Off-cycle refrigerant migration is likely to occur when the compressor is located at the coldest part of the installation, when the system uses a bleed-type expansion device, or if liquid could migrate from the evaporator into the compressor sump by gravity. If too much liquid refrigerant accumulates in the sump, it will saturate the oil and lead to a flooded start. When the compressor starts, the refrigerant evaporates abruptly under the sudden decrease of the bottom shell

pressure, causing the oil to foam. In extreme situations, this might result in too much oil leaving the compressor, which must be avoided as it causes irreversible damages due to possible lack of lubrication.

LLZ scroll compressors can tolerate occasional flooded starts as long as the system has been evaluated.

A suitable test to evaluate the risk of off-cycle migration is the following:• Stabilise the non running system at 5°C

ambient temperature.• Raise the ambient temperature to 20°C and

keep it for 10 minutes.• Start the compressor and monitor sump

temperature, sight glass indication and sound level.

The presence of liquid in the crankcase can be easily detected by checking the sump level through the oil sight glass. Foam in the oil sump indicates a flooded start.A noisy start, oil loss from the sump and sump cool down are indications for migration. Depending on the amount of migration graduate measures shall be taken:• Crankcase heater• Liquid line solenoid valve• Pump down cycle

Note: for special conditions such as low ambient temperature, low load operation or brazed plate heat exchangers please refer to corresponding sections.

Recommended Required No test or additional safeties requiredREC

BELOW charge limit ABOVE charge limit

Packaged units No test or additional safeties requiredOff cycle migration test

Liquid flood back test

System with remote heat exchanger Off cycle migration testOff cycle migration test Liquid flood back testREC REQ

REQ

REQ

REQ

Crankcase heater: when the compressor is idle, the oil temperature in the sump must be maintained at no lower than 10 K above the saturation temperature of the refrigerant on the low-pressure side. This requirement ensures that the liquid refrigerant is not accumulating in the sump. A crankcase heater is only effective if capable of sustaining this level of temperature

difference. Tests must be conducted to ensure that the appropriate oil temperature is maintained under all ambient conditions (temperature and wind). Below -5°C ambient temperature and a wind speed of above 5m/sec, it is recommended to thermally insulate the heaters in order to limit the surrounding energy losses.

Depending on test results, crankcase heaters, Liquid Line Solenoid Valve, pump down or suction accumulator must be applied (see below)

REQ

25FRCC.PC.025.A6.02

Application Guidelines

Page 26: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

System design recommendations

Due to the Danfoss scroll compressors inherent ability to handle liquid refrigerant, crankcase heaters are not required when the system charge does not exceed the recommended maximum charge.

Since the total system charge may be undefined, a crankcase heater is recommended on all systems with remote heat exchangers. In addition, any system containing a refrigerant charge in excess of the maximum recommended system charge for compressors requires a crankcase heater.

Belt-type crankcase heater accessories are available from Danfoss (see section “Spare parts and accessories”).

The heater must be energized whenever the compressor is off.

Provide separate electrical supply for the heaters so that they remain energized even when the machine is out of service (e.g. seasonal shutdown).

It is recommended that the heater be turned on for a minimum of 12 hours prior to starting the compressor.

Optimum location area

Pump-down cycle: Once the system has reached its set point and is about to shut off, the LLSV on the liquid line closes. The compressor then pumps the majority of the refrigerant charge into the high pressure side before the system stops on the low pressure pump-down switch. This step reduces the amount of charge on the low side in order to prevent off-cycle migration.

A pump-down cycle represents one of the most effective ways to protect against the off-cycle migration of refrigerant; however it is only convenient to apply on application with thermostatic control.

Rack application with pressostatic control can use timer delay to empty the evaporators before the stop. Time should be carefully set to not interfere with the low safety pressure switch.

For low pressure pump-down switch settings, refer to section “High and low pressure protection”. For suggested wiring diagrams, please see section “Wiring diagram”.

Under certain conditions, the internal valve may not completely seal, and due to the refrigerant back flow the compressor might restart during pump-down applications. Repeated short cycling can result in a compressor breakdown. It is

recommended to install an external magnetic check valve (such as Danfoss Part No. 120Z5046) close to the compressor’s discharge connector so the discharge volume is minimized.

A magnetic check valve is recommended for this as it offers the best solution regarding minimal required and maximal pressure drop over the wide application envelope of the LLZ scroll compressors. If a Danfoss NRV check valve is applied it has to be carefully selected for the specific operation conditions of the individual system.

Tests for pump down cycle approval:• As the pump-down switch setting is inside the

application envelope, tests should be carried out to check unexpected cut-out during transient conditions (i.e. defrost – cold starting). When unwanted cut-outs occur, the low pressure pump-down switch can be delayed. In this case a low pressure safety switch without any delay timer is mandatory.

• While the thermostat is off, the number of pressure switch resets should be limited to avoid short cycling of the compressor. Use dedicated wiring and an additional relay which allows for one shot pump-down.

Liquid line solenoid valve (LLSV): This feature is very convenient and can be used on all types of applications.

An LLSV is used to isolate the liquid charge in the high pressure side, thereby preventing against

charge transfer or excessive migration to the compressor during off-cycles. The quantity of refrigerant remaining in the low-pressure side of the system can be further reduced by using a pump-down cycle in association with the LLSV.

26 FRCC.PC.025.A6.02

Application Guidelines

Page 27: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

System design recommendations

Suction accumulator: a suction accumulator offers protection against refrigerant flood back at start-up, during operations or defrosting by trapping the liquid refrigerant upstream from the compressor. The suction accumulator also protects against off-cycle migration by providing additional internal free volume to the low side of the system.

A suction accumulator must be carefully dimensioned, taking into account the refrigerant charge as well as the gas velocity in the suction line. Depending on the operating conditions it may happen that the recommended connections of the accumulator are one size smaller than the suction line.

Liquid flood back During normal operation, refrigerant enters the compressor as a superheated vapour. Liquid flood back occurs when a part of the refrigerant entering the compressor is still in liquid state.

A continuous liquid flood back will cause oil dilution and, in extreme situations, lead to lack of lubrication and high rate of oil leaving the compressor.

Liquid flood back test: repetitive liquid flood back testing must be carried out under TXV threshold operating conditions-a high pressure ratio and minimum evaporator load, along with the measurement of suction superheat, oil sump temperature and discharge gas temperature.

During operations, liquid flood back may be detected by measuring either the oil sump temperature or the discharge gas temperature. If at any time during operations, the oil sump temperature drops to within 10K or less above the saturated suction temperature, or should

the discharge gas temperature be less than 35K above the saturated discharge temperature, this indicates liquid flood back.

Continuous liquid flood back can occur with a wrong dimensioning, a wrong setting or malfunction of the expansion device or in case of evaporator fan failure or blocked air filters.

A suction accumulator providing additional protection as explained hereunder can be used to solve light continuous liquid flood back.

The pump-down allows to store all the refrigerant in the high pressure side circuit. On unitary or close-coupled systems, where the system refrigerant charge is expected to be both correct and definable the entire system charge may be stored in the condenser during pump-down if all components have been properly sized.

Other application needs a liquid receiver to store the refrigerant.

Receiver dimensioning requires special attention. The receiver shall be large enough to contain part of the system refrigerant charge but it shall not be dimensioned too large. A large receiver easily leads to refrigerant overcharging during maintenance operation.

27FRCC.PC.025.A6.02

Application Guidelines

Page 28: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Specific application recommendations

Low ambient application

Low ambient operations It is recommended that the unit be tested and monitored at minimum load and low ambient conditions as well. The following considerations should be taken into account to ensure proper system operating characteristics.

The expansion device should be sized to ensure proper control of the refrigerant flow into the evaporator. An oversized valve may result in erratic control. This consideration is especially important in manifolded units where low load conditions may require the frequent cycling of compressors. This can lead to liquid refrigerant entering the compressor if the expansion valve does not provide stable refrigerant super-heat control under varying loads.

The superheat setting of the expansion device should be sufficient to ensure proper superheat levels during low loading periods. A minimum of 5 K stable superheat is required.

Head pressure control under low ambient conditions: Several possible solutions are available to prevent the risk of compressor to vacuum and low pressure differential between the suction and discharge pressures.

In air-cooled machines, cycling the fans with a head pressure controller will ensure that the fans remain off until the condensing pressure has reached a satisfactory level. Variable speed fans can also be used to control the condensing pressure. In water-cooled units, the same can be performed using a water regulator valve that is also operated by head pressure, thereby ensuring that the water valve does not open until the condensing pressure reaches a satisfactory level.The minimum condensing pressure must be set at the minimum saturated condensing temperature shown in the application envelopes.

Under very low ambient conditions, in which testing has revealed that the above procedures might not ensure satisfactory condensing and suction pressures, the use of a head pressure control valve is recommended. Note: This solution requires extra refrigerant charge, which can introduce other problems. A non-return valve in the discharge line is recommended and special care should be taken when designing the discharge line.

For further information, please contact Danfoss.

Low ambient start-up Under cold ambient conditions (<0°C), upon start-up the pressure in the condenser may be so low that a sufficient pressure differential across the expansion device cannot be developed to properly feed the evaporator.

As a result, the compressor may go into a deep vacuum, which can lead to compressor failure due to internal arcing and instability in the scroll wraps. Under no circumstances should the compressor be allowed to operate under vacuum. The low-pressure control must be set in accordance with the table on section “High and low pressure protection” in order to prevent this from happening.

Early feeding of the evaporator and management of the discharge pressure could help to attenuate these effects.

Low pressure differentials can also cause the expansion device to “hunt” erratically, which might cause surging conditions within the evaporator, with liquid spillover into the compressor. This effect is most pronounced during low load conditions, which frequently occur during low ambient conditions.

Unlike the reciprocating compressor, a scroll does not have dead volume. Neither does it have a suction valve causing pressure drop. As a result a scroll compressor has a high volumetric efficiency even at low suction pressure. In systems such as ice makers and milk cooling tanks this high capacity at low temperature shortens the cooling time.

When moving from a reciprocating compressor to a scroll compressor, the selection shall always be made based on cooling capacity at the application rating point. Never make a selection based on equivalent displacement.

Scroll and reciprocating

28 FRCC.PC.025.A6.02

Application Guidelines

Page 29: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Specific application recommendations

Low load operations The compressor should be run for a minimum period to ensure that the oil has sufficient time to properly return to the compressor sump and

that the motor receives enough cooling under conditions of lowest refrigerant mass flow.

Brazed plate heat exchangers

A brazed plate heat exchanger needs very little internal volume to satisfy the heat transfer requirements. Consequently, the heat exchanger offers very little internal volume for the compressor to draw vapour from the suction side. The compressor can then quickly enter into a vacuum condition. It is therefore important that the expansion device be sized correctly and that a sufficient pressure differential across the expansion device be available to ensure adequate refrigerant feed into the evaporator. This aspect is of special concern when operating the unit under low ambient and load conditions. For further information on these conditions, please refer to the previous sections.

Due to the small volume of the brazed plate heat exchanger, no pump-down cycle is normally required. The suction line running from the heat exchanger to the compressor must be trapped to avoid refrigerant migration to the compressor.

When using a brazed plate condenser heat exchanger, a sufficient free volume for the discharge gas to accumulate is required in order to avoid excess pressure build-up. At least one meter of discharge line is necessary to generate this volume. To help reduce the discharge gas volume immediately after start-up, the supply of cooling water to the heat exchanger may be opened before the compressor starts, to remove superheat and condense the incoming discharge gas more quickly.

Water utilising systems

Defrost cycle

Apart from residual moisture in the system after commissioning, water could also enter the refrigeration circuit during operation. Water in the system shall always be avoided. Not only because it can quickly lead to electrical failure, sludge in sump and corrosion but in particular because it can cause serious safety risks.

Common causes for water leaks are corrosion and freezing.

Corrosion: Materials in the system shall be compliant with water and protected against corrosion.

Freezing: When water freezes into ice its volume expands which can damage heat exchanger walls and cause leaks. During off periods water inside heat exchangers could start freezing when ambient temperature is lower than 0°C. During on periods ice banking could occur when the circuit is running continuously at too low load. Both situations should be avoided by connecting a pressure and thermostat switch in the safety line.

In refrigeration system applications, there are different defrost methods, such as electric heating defrost, hot gas bypass defrost, reversible defrost etc. For the systems which use hot gas bypass or reversible defrost method, suction accumulator is necessary as a result of the possibility of a substantial quantity of liquid refrigerant remaining in the evaporator.

This liquid refrigerant can then return to the compressor, either flooding the sump or as a dynamic liquid slug when the cycle switch back to normal cooling operations. Sustained and repeated liquid slugging and flooding can seriously impair the oil’s ability to lubricate the compressor bearings. In such cases a suction accumulator is a must.

29FRCC.PC.025.A6.02

Application Guidelines

Page 30: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Sound and vibration management

Running sound level

Stopping sound level

Sound generation in a refrigeration system

Compressor sound radiation

LLZ are designed with features to reduce the sound level when a compressor is running.

Average sound levels below is at ARI LBP condition.

LLZ scroll compressor have a unique discharge valve design that minimizes stopping noise. This results in very low shutdown sound.

Typical sound and vibration in refrigeration systems encountered by design and service engineers may be broken down into the following three source categories.

Sound radiation: This generally takes an airborne path.

Mechanical vibrations: These generally extend along the parts of the unit and structure.

Gas pulsation: This tends to travel through the cooling medium, i.e. the refrigerant.

The following sections will focus on the causes and methods of mitigation for each of the above sources.

For sound radiating from the compressor, the emission path is airborne and the sound waves are travelling directly from the machine in all directions.

The LLZ scroll compressors are designed to be quiet and the frequency of the sound generated is pushed into the higher ranges, which not only are easier to reduce but also do not generate the penetrating power of lower-frequency sound.

Use of sound-insulation materials on the inside of unit panels is an effective means of substantially reducing the sound being transmitted to the outside. Ensure that no components capable of transmitting sound/vibration within the unit come into direct contact with any non insulated parts on the walls of the unit.Due to the unique design of a full-suction gas and oil cooled motor, compressor body insulation across its entire operating range is possible.

During start-up transients it is natural for the compressor sound level to be slightly higher than during normal running. LLZ scroll compressors exhibit very little increased start-up transient sound. If a three-phase model is miswired, the compressor will run in reverse. Reverse

compressor rotation is characterised by an objectionable sound. To correct reverse rotation, disconnect power and switch any two of the three power leads at the unit contactor. Never switch leads at the compressor terminals.

Starting sound level

Model50 Hz 60 Hz

Sound power (dBA)Without jacket

Sound power (dBA)With jacket

Sound power (dBA)Without jacket

Sound power (dBA)With jacket

LLZ013 78 70 80 72

LLZ015 80 72 83 75

LLZ018 83 73 84 74

LLZ024 85 75 86 76

LLZ 034 85 77 86 78 Note: LLZ034 data is preliminary

30 FRCC.PC.025.A6.02

Application Guidelines

Page 31: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Sound and vibration management

Mechanical vibrations Vibration isolation constitutes the primary method for controlling structural vibration. LLZ scroll compressors are designed to produce minimal vibration during operations. The use of rubber isolators on the compressor base plate or on the frame of a manifolded unit is very effective in reducing vibration being transmitted from the compressor(s) to the unit. Rubber grommets are supplied with all LLZ scroll compressors. Once the supplied rubber grommets have been properly mounted, vibration transmitted from the compressor base plate to the unit are held to a strict minimum. In addition, it is

extremely important that the frame supporting the mounted compressor be of sufficient mass and stiffness to help dampen any residual vibration potentially transmitted to the frame. The tubing should be designed so as to both reduce the transmission of vibrations to other structures and withstand vibration without incurring any damage. Tubing should also be designed for three-dimensional flexibility. For more information on piping design, please see the section entitled "Essential piping design considerations".

Gas pulsation The LLZ scroll compressors have been designed and tested to ensure that gas pulsation has been minimized for the most commonly encountered refrigeration pressure ratio. On installations where the pressure ratio lies beyond the typical range, testing should be conducted under all expected conditions and operating

configurations to ensure that minimum gas pulsation is present. If an unacceptable level is identified, a discharge muffler with the appropriate resonant volume and mass should be installed. This information can be obtained from the component manufacturer.

31FRCC.PC.025.A6.02

Application Guidelines

Page 32: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Installation

Each LLZ scroll compressor is shipped with printed Instructions for installation. These Instructions can also be downloaded from our

website www.danfoss.com or directly from:http://instructions.cc.danfoss.com

Compressor handling and storage

Compressor holding charge

Compressors are provided with a lifting lug. This lug should always be used to lift the compressor. Once the compressor is installed, the lifting lug should never be used to lift the complete installation. The compressor must be handled

with caution in the vertical position, with a maximum inclination of 15° from vertical. Store the compressor between -35°C and 55°C, not exposed to rain or corrosive atmosphere.

Each compressor is shipped with a nominal dry nitrogen holding charge between 0.4 bar and 0.7 bar, and is sealed with elastomer plugs. The plugs should be removed with care to avoid oil loss when the holding charge is released. Remove the suction plug first and the discharge plug

afterwards. The plugs shall be removed only just before connecting the compressor to the installation in order to avoid moisture entering the compressor. When the plugs are removed, it is essential to keep the compressor in an upright position to avoid oil spillage.

System cleanliness The refrigeration system, regardless of the type of compressor used, will only provide high efficiency and good reliability, along with a long operating life, if the system contains solely the refrigerant and oil it was designed for. Any other substances within the system will not improve performance and, in most cases, will be highly detrimental to system operations.

The presence of non-condensable substances and system contaminants, such as metal shavings, solder and flux, have a negative impact on compressor service life. Many of these contaminants are small enough to pass through

a mesh screen and can cause considerable damage within a bearing assembly. The use of highly hygroscopic PVE oil in LLZ scroll compressors requires that the oil be exposed to the atmosphere just as little as possible.

During the manufacturing process, circuit contamination may be caused by:• Brazing and welding oxides• Filings and particles from the removal of burrs in pipe-work• Brazing flux• Moisture and air.

Compressor mounting Maximum inclination from the vertical plane, while operating must not exceed 7 degrees. All compressors are delivered with four rubber grommets and metal sleeves. Compressors

must always be mounted with these grommets. Recommended torque for mounting bolts: 11 Nm (±1 Nm).

32 FRCC.PC.025.A6.02

Application Guidelines

Page 33: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Installation

Moisture obstructs the proper functioning of the compressor and the refrigeration system.

Air and moisture reduce service life and increase condensing pressure, and cause excessively high discharge temperatures, which can destroy the lubricating properties of the oil. Air and moisture also increase the risk of acid formation, giving rise to copper platting. All these phenomena can cause mechanical and electrical compressor failure.

For these reasons it is important to perform a vacuum dehydration on the system to remove all residual moisture from the pipe-work after assembly;

LLZ scroll compressors are delivered with <100 ppm moisture level. The required moisture level in the circuit after vacuum dehydration must be <100 ppm for systems with an LLZ scroll compressor.

• Never use the compressor to evacuate the system.

• Connect a vacuum pump to both the LP and HP sides.

• Evacuate the system to a pressure of 500 μm Hg (0.67 mbar) absolute.

• Do not use a megohm meter nor apply power to the compressor while it is under vacuum as this may cause internal damage.

Vacuum evacuation and moisture removal

Refrigerant charging It is recommended that system charging be done using the weighed charge method, adding refrigerant to the high side of the system. Charging the high and low sides of a system with gas simultaneously at a controlled rate is also an acceptable method. Do not exceed the recommended unit charge, and never charge liquid to the low side.

Vacuum or charge from one side can seal the scrolls and result in a non-starting compressor. When servicing, always ensure that LP/HP pressures are balanced before starting the compressor. Please note the dielectric test could never be carried under vacuum state.

Be sure to follow all government regulations regarding refrigerant reclamation and storage.

Liquid line filter driers A properly sized and type of drier is required. Important selection criteria include the driers water content capacity, the system refrigeration capacity, and the system refrigerant charge. The drier must be able to reach and maintain a moisture level of 50 ppm end point dryness (EPD). Danfoss recommends DML (100% molecular sieve) driers for LLZ scroll compressors (R404A, R507) with PVE oil.

For servicing of existing installations where acid formation may be present, the Danfoss DCL solid core filter drier containing activated alumina is recommended.

After burn out, remove and replace the liquid line filter drier and install a Danfoss type DAS burnout drier of the appropriate capacity. Refer to the DAS drier instructions and technical information for correct use of the burnout drier on the liquid line.

Insulation resistance and dielectric strength

Insulation resistance must be higher than 1 megohm when measured with a 500 volt direct current megohm tester.

Each compressor motor is tested at the factory with a high potential voltage (hi-pot) that exceeds the UL requirement both in potential and in duration. Leakage current is less than 0.5 mA.

LLZ scroll compressors are configured with the pump assembly at the top of the shell, and the motor below. As a result, the motor can be partially immersed in refrigerant and oil. The presence of refrigerant around the motor windings will result in lower resistance

values to ground and higher leakage current readings. Such readings do not indicate a faulty compressor, and should not be cause for concern.

In testing insulation resistance, Danfoss recommends that the system be first operated briefly to distribute refrigerant throughout the system. Following this brief operation, retest the compressor for insulation resistance or current leakage. Please note the dielectric test could never be carried under vacuum state.

Never reset a breaker or replace a fuse without first checking for a ground fault (a short circuit to ground). Be alert for sounds of arcing inside the compressor.

33FRCC.PC.025.A6.02

Application Guidelines

Page 34: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Ordering information and packaging

Industrial pack

Compressors are packed individually in a cardboard box. They can be ordered in any quantity. Minimum ordering quantity = 1. As far as possible, Danfoss will ship the boxes on full pallets of six compressors according below table.

Each box also contains the following accessories:• 4 grommets• 4 assemblies of self tapping US thread bolts,

washers and sleeves• 4 additional sleeves• 1 screw for earth connection• Depending on model and shipping type a run

capacitor may be included (see table).

Compressors are not packed individually but are shipped all together on one pallet. They can be ordered in quantities of full pallets only, multiples of twelve or sixteen compressors, according to the below table.

Each industrial pack pallet contains the following accessories:• 4 grommets per compressor• 4 sleeves per compressor

Packaging

Single pack

Packaging details

Compressor models Length(mm)

Width(mm)

Height(mm)

Gross weight(kg)

LLZ013 1170 815 730 381

LLZ015 1170 815 730 381

LLZ018 1170 815 730 387

LLZ024 1170 815 775 405

LLZ034 1170 815 817 437

Compressor models Nbr* Length

(mm)Width (mm)

Height (mm)

Gross weight

(kg)

Static stacking pallets

LLZ013 12 1170 815 665 538 4

LLZ015 12 1170 815 665 538 4

LLZ018 12 1170 815 665 550 4

LLZ024 12 1170 815 720 586 4

LLZ034 12 1170 815 817 651 4

* nbr: number of compressors per packNote: LLZ034 data is preliminary

Note: Gross weight here including 6 single pack compressors LLZ034 data is preliminary

Danfoss pallets

Code number 121L….

Pack type Industrial pack Single pack

Compressors per pallet 12 6 *

Static stacking of pallets ** 4 4

Ship

ped

acce

ssor

ies

Run capacitor (for single phase models) Not included Included

Screw for earth connection Included Included

4 grommets per compressor Included Included

4 assemblies of self tapping US thread bolt + washer + sleeve per compressor Not included Included

4 extra sleeves per compressor Included Included

2 rotolock nuts for suction and discharge fiting connection Included Included

3 sleeves for suction, discharge and economizer fitting connection Included Included

3 teflon seals for suction, discharge and economizer fitting connection Included Included

* Quantity for full pallets. Single packs can be ordered per 1.** Stacking only allowed for full pallets with identical products per pallet

34 FRCC.PC.025.A6.02

Application Guidelines

Page 35: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Ordering information and packaging

Single pack

Industrial pack

Compressors Model variation Connections Features Voltage

code 2Voltage code 4

Voltage code 9

Danfosspallet

LLZ013 T Q 9 121L9519 121L9517 121L9531

LLZ015 T Q 9 121L9515 121L9513 121L9529

LLZ018 T Q 9 121L9511 121L9509 121L9527

LLZ024 T Q 9 121L9507 121L9505 121L9525

LLZ034 T Q 9 N/A 121L9521 121L9533

Note: LLZ034 data is preliminary

Compressors Model variation Connections Features Voltage

code 2Voltage code 4

Voltage code 9

Danfosspallet

LLZ013 T Q 9 121L9518 121L9516 121L9530

LLZ015 T Q 9 121L9514 121L9512 121L9528

LLZ018 T Q 9 121L9510 121L9508 121L9526

LLZ024 T Q 9 121L9506 121L9504 121L9524

LLZ034 T Q 9 N/A 121L9520 121L9532

Note: LLZ034 data is preliminary

35FRCC.PC.025.A6.02

Application Guidelines

Page 36: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Spare parts and accessories

Magnetic discharge non return valve

Lubricant

Discharge temperature protection

Crankcase heater

Type Code No Description Application Packaging Pack Size

7750009 Discharge thermostat kit All models Multipack 10

7973008 Discharge thermostat kit All models Industry pack 50

Type Code No Description Application Packaging Pack Size

120Z5046 Magnetic discharge non return valve All models Multipack 6

Type Code No Description Application Packaging Pack Size

FVC32D 120Z5035 PVE lubricant, 2 litre can LLZ Multipack 12

Type Code No Description Application Packaging Pack Size

120Z5040 Belt type crankcase heater, 70 W, 240 V, CE mark, UL (Wire length: 1270 mm)

All models

Multipack 4

120Z5041 Belt type crankcase heater, 70 W, 400/460 V, CE mark, UL (Wire length: 1270 mm) Multipack 4

120Z5042 Belt type crankcase heater, 70 W, 575 V, CE mark, UL (Wire length: 1270 mm) Multipack 4

120Z0059 Belt type crankcase heater, 65 W, 230V, CE mark, UL (Wire length: 1000 mm) Multipack 6

120Z0060 Belt type crankcase heater, 65 W, 400 V, CE mark, UL (Wire length: 1000 mm) Multipack 6

36 FRCC.PC.025.A6.02

Application Guidelines

Page 37: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Spare parts and accessories

Mounting hardware

IP54 upgrade kit

Acoustic hood

Type Code No Description Application Packaging Pack Size

120Z5067

Mounting kit for 1 scroll compressor including 4 grommets, 4 sleeves, 4 bolts, 4 washers, rotolock connection kit for suction, discharge and economizer fitting for 1 scroll compressor including 3 Teflon seals, 2 nuts, 3 sleeves.

LLZ013/015/018 single 1

120Z5068

Mounting kit for 1 scroll compressor including 4 grommets, 4 sleeves, 4 bolts, 4 washers, rotolock connection kit for suction, discharge and economizer fitting for 1 scroll compressor including 3 Teflon seals, 2 nuts, 3 sleeves.

LLZ024/034 single 1

Type Code No Description Application Packaging Pack Size

118U0057 IP54 upgrade kit All models Multipack 6

Type Code No Description Application Packaging Pack Size

120Z5052 Acoustic hood LLZ013-015-018 Single pack 1

120Z5053 Acoustic hood LLZ024 Single pack 1

120Z5055 Acoustic hood LLZ034 Single pack 1

37FRCC.PC.025.A6.02

Application Guidelines

Page 38: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Updates

Previous version Current version

Page36: Lubricant, Type - 320HV, Code No - 120Z5034, Description - PVE lubricant, 0.95 litre can.

Page36: Lubricant, Type - FVC32D, Code No - 120Z5035, Description - PVE lubricant, 2 litre can.

38 FRCC.PC.025.A6.02

Application Guidelines

Page 39: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,
Page 40: Application guidelines - files.danfoss.comfiles.danfoss.com/technicalinfo/dila/17/FRCC.PC.025.A6.02-LLZ-Mar... · Essential piping design recommendations ... process flexibility,

Danfoss Commercial Compressors is a worldwide manufacturer of compressors and condensing units for refrigeration and HVAC applications. With a wide range of high quality and innovative products we help your company to find the best possible energy efficient solution that respects the environment and reduces total life cycle costs.

We have 40 years of experience within the development of hermetic compressors which has brought us amongst the global leaders in our business, and positioned us as distinct variable speed technology specialists. Today we operate from engineering and manufacturing facilities spread across three continents.

FRCC.PC.025.A6.02 - March 2015 - Replaces FRCC.PC.025.A5.02 - March 2015 © Copyright Danfoss | Commercial Compressors | 2015.03

Our products can be found in a variety of applications such as rooftops, chillers, residential air conditioners, heatpumps, coldrooms, supermarkets, milk tank cooling and industrial cooling processes.

http://cc.danfoss.com

Danfoss Inverter Scrolls

Danfoss Turbocor Compressors

Danfoss Scrolls

Danfoss Optyma Condensing Units

Secop Compressors for Danfoss

Danfoss Maneurop Reciprocating Compressors

Danfoss Commercial Compressors, BP 331, 01603 Trévoux Cedex, France | +334 74 00 28 29