Regency TAFE, SA

An evaluation of the effects of PermaFrost treatment on a Fujitsu Heat Pump July 2008

Prepared by Andrew Pang Andrew Pang & Associates Pty Ltd Phone: 0438 188 180 Facsimile: 9331 0898 E-mail: bnpang@aapt.net.au for Enrico Sgarbi enACon Holdings Pty Ltd Lobethal, SA

INTRODUCTION

The aim of this report is to examine the effects of PermaFrost upon the refrigeration system of a two year old Fujitsu heat pump, Model AOT12LSAC. This unit is an inverter type that uses refrigerant R-410A.

METHODOLOGY

The testing was conducted in a laboratory at Regency TAFE, SA under control conditions. The indoor unit was placed in a room with two operating electric heaters to maintain a constant room temperature. The total heating load of the heaters was 2.25 kW. The condensing unit was placed in another room with an operating air conditioning unit to maintain a constant ambient temperature. The testing procedure included an analysis of the refrigeration system on two occasions: 1) Before the addition of PermaFrost, and 2) After addition of the product.

To measure the performance of the refrigeration system, an “ETM” refrigeration system analyzer was used to data log the operating conditions of the systems during testing. For each test, the analyser collected the data on the following operating conditions over a 10 hour period at one minute interval for the same time period of the day:

• Power input • Cooling capacity • Coefficient of Performance, COP • Compressor discharge temperature • Evaporating temperature and pressure • Condensing temperature and pressure • Room temperature • Ambient temperature

TESTING The refrigeration system of the Fujitsu heat pump was first tested on July 3, 2008 before PermaFrost was introduced into the system and then on July 4, 2008 after the treatment. The two “yardsticks” for comparing the performance of the refrigeration system for the two tests are the ambient temperature and room temperature. The variation in the mean ambient temperature between the pre-test and the post-test was 0.10 %. The variation in the mean room temperature between the pre-test and the post-test was 1.14 %. These variations can be considered as insignificant and, hence, the ambient temperature and room temperature can be assumed to be constant for both tests.

The mean power consumption for the period of the pre-test was 6.2 kWh. The mean power consumption for the period of the post-test was 5.6 kWh.

RESULTS OF TESTING Detailed results of the operating conditions are provided in the following charts, all found in Appendix A: 1. Pre-treatment Test (July 3, 2008) Chart 1A: Cooling Capacity, Power Input & Coefficient of Performance Chart 2A: Ambient, Room and Evaporating Temperatures Chart 3A: Condensing and Compressor Discharge Temperatures Chart 4A: Evaporator & Condenser Pressures 2. Post-treatment Test (July 4, 2008) Chart 1B: Cooling Capacity, Power Input & Coefficient of Performance Chart 2B: Ambient, Room and Evaporating Temperatures Chart 3B: Condensing and Compressor Discharge Temperatures Chart 4B: Evaporator & Condenser Pressures Observations A comparison of the mean operating conditions for each of the tests are summarised in table below: Test Results : Operating Mean Values

Pre-treatment Post-treatment % change

Cooling Capacity (kW) 3.16 3.71 17.41

Power Input (kW) 0.62 0.56 -9.68

Coefficient of Performance, COP Percentage Improvement 31.05

Discharge Temperature (°C) 58.11 56.98 -1.94

Evaporating Temperature (°C) 15.37 16.30 6.05

Condensing Temperature (°C) 51.11 50.94 -0.33

Condensing Pressure (Bar Gauge) 22.59 22.50 -0.40

Evaporating Pressure (Bar Gauge) 8.59 8.84 2.91

Room Temperature (°C) 20.23 20.46 1.14

Ambient Temperature (°C) 30.74 30.71 -0.10

From this table, a number of observations can be made about the effects of PermaFrost on the Fujitsu heat pump:

• Cooling capacity increased by 17.41 % in the post-treatment test. This indicates a significant improvement in heat transfer in the evaporator.

• Power input decreased by 9.68% in the post-treatment test. This indicates a significant decrease in power consumption by the compressor.

• The COP (a ratio of the cooling capacity and power input) increased by 31.05% in the post-treatment test. This indicates a significant improvement in the overall system performance.

• The compressor discharge temperature decreased by 1.94%. • The increase in evaporating temperature and pressure further indicates

improvement in heat transfer in the evaporator. • The variation in the condensing temperature between the pre-test and the

post-test was 0.33 %. The variation in the condensing pressure between the pre-test and the post-test was 0.4 %. These variations can be considered as insignificant and, hence, the condensing temperature and pressure can be assumed to be constant for both tests.

CONCLUSION The tests carried out on the Fujitsu heat pump, Model AOT12LSAC indicated an improvement in the cooling capacity of 17.4%, a decrease in power input of 9.7% and an overall increase in system performance of 31% after treatment with PermaFrost. The increase in cooling capacity and system performance will result in the compressor using less energy to achieve the same cooling effect on the unit as prior to treatment with Permafrost. The tests showed that for the 10-hour run time on the unit with the heaters in the room as simulated load the power consumption decrease from 6.2 kWh to 5.6 kWh. This represents an energy saving of 9.7%. In practice, the load in the room will vary rather than remain constant as during the tests with the simulated heat load, the heat pump will cycle on and off as the room reaches the set temperature. Hence, with the increase in cooling capacity and system performance after treatment with PermaFrost, the compressor actual run time will be shorter and the energy saving will be greater than the 9.7% achieved during the post test. The salient results are summarised in the bar graphs in Appendix B.

 

 

Pre Treatment Test

July 3, 2008

Appendix A

Chart 1A - TAFE Regency Park SA - Fujitsu R410A Inverter

10

POWER INPUT [kW]  COOLING CAPACITY [kW]

Chart 1A TAFE, Regency Park SA Fujitsu R410A InverterPerformance Measurement, Pre PermaFrost

Mean value = 3.16 kWMean value = 0.62 kWMean value = 3.16

8

9Before PermaFrost

6

7

4

5

Value

2

3

0

1

July 3, 2008

Chart 2A - TAFE Regency Park SA ‐ Fujitsu R410A Inverter

40

ROOM TEMP °C  AMBIENT TEMP °C  EVAP TEMP °C 

Chart 2A - TAFE, Regency Park SA ‐ Fujitsu R410A InverterOperating Temperatures, Pre PermaFrost

Mean value = 20.23 °C Mean value = 15.37 °C Mean value = 30.74 °C

B f P F

35

Before PermaFrost

30

25

Temp [°C]

1

20

10

15

July 3, 2008

Chart 3A - TAFE Regency Park SA ‐ Fujitsu R410A Inverter

70

COND °C  DISCH °C 

Chart 3A - TAFE, Regency Park SA ‐ Fujitsu R410A InverterOperating Temperatures, Pre PermaFrost

Mean value = 51.11 °C Mean value =58.11 °C

65

Before PermaFrost

60

55

Temp °C

50

40

45

July 3, 2008

Chart 4A - TAFE Regency Park SA ‐ Fujitsu R410A Inverter

30

EVAP PRESS Bar COND PRESS Bar

Chart 4A - TAFE, Regency Park SA ‐ Fujitsu R410A InverterOperating Temperatures, Pre PermaFrost

Mean value = 8.59 Bar Mean value = 22.59 Bar

25

Before PermaFrost

20

15

Temp °C

10

0

5

July 3, 2008

Post Treatment Test

July 4, 2008

Appendix A

Chart 1B - TAFE Regency Park SA ‐ Fujitsu R410A Inverter

10

POWER INPUT [kW]  COOLING CAPACITY kW 

Chart 1B - TAFE, Regency Park SA ‐ Fujitsu R410A InverterPerformance Measurement, Post PermaFrost

Mean value = 3.71 Mean value = 0.56 kW Mean value = 3.71 kW

Aft P F t

8

9

AfterPermaFrost

6

7

4

5

Value

2

3

0

1

July 4, 2008

Chart 2B - TAFE Regency Park SA ‐ Fujitsu R410A Inverter

40

ROOM TEMP °C  AMBIENT TEMP °C  EVAP TEMP °C 

Chart 2B - TAFE, Regency Park SA ‐ Fujitsu R410A InverterOperating Temperatures, Post PermaFrost

Mean value = 20.23 °C Mean value = 16.3 °C Mean value = 30.71 °C

35

AfterPermaFrost

30

25

Temp [°C]

15

20

10

July 4, 2008

Chart 3B - TAFE Regency Park SA ‐ Fujitsu R410A Inverter

65

COND °C  DISCH °C 

Chart 3B - TAFE, Regency Park SA ‐ Fujitsu R410A InverterOperating Temperatures, Post PermaFrost

Mean value =50.94 °C Mean value = 56.98 °C

f

60

AfterPermaFrost

55

50Tem

p °C

45

40

July 4, 2008

Chart 4B - TAFE Regency Park SA ‐ Fujitsu R410A Inverter

30

EVAP PRESS Bar COND PRESS Bar

Chart 4B - TAFE, Regency Park SA ‐ Fujitsu R410A InverterOperating Temperatures, Post PermaFrost

Mean value = 8.84 Bar Mean value = 22.5 Bar

25

AfterPermaFrost

20

15

Temp °C

5

10

0

July 4, 2008

Performance Comparison

Pre:

July 3, 2008

&

Post: July 4, 2008

Appendix B 

TAFE Regency Park SA - Fujitsu R410A Inverter

3.8

Cooling Capacity (kW) Linear (Cooling Capacity (kW))

TAFE, Regency Park SA Fujitsu R410A InverterPre & Post PermaFrost Comparison, Cooling Capacity

3.71

3.6

3.7

3.5

3.6

3.3

3.4

kW

3.163.1

3.2

2.9

3

2.8

Pre‐treatment Post‐treatment

TAFE Regency Park SA Fujitsu R410A Inverter

8

Cooling Capacity (kW) Power Input (kW)

TAFE, Regency Park SA ‐ Fujitsu R410A InverterPre & Post PermaFrost Comparison, System Performance

7

5

6

3.714

Value

3.16

3

0.62 0 561

2

0.56

0

Pre‐treatment Post‐treatment