Trouble Shooting Guide York

MINISPLIT

Trouble Shooting Guide

TROUBLESHOOTING 24/2/01, 18:441

2Table of Contents

Descriptions

General Truble Shooting.........................................................................3

Electrical Trouble Shooting.....................................................................5

PC Board Trouble Shooting..................................................................15

MiniSplit unit startup Checklist..............................................................19

Page


Too much or too little refrigerantAir or incondensibles in refrigerant circuitFaulty compressorPower supply voltage too high or too lowFaulty condenser (single phase models)Faulty thermostatRestriction in the refrigeration circuitFrostec or plugged expansion devicePoor airflow on indoor or outdoor unit

Faulty power supplyChangeover valve damaged or blocked open(heat pump units)

Remove charge, evacuate and rechargeRemove charge, evacuate and rechargeDetemine the cause and replace compressorSolve the problemDetemine the cause and replaceReplaceFind restriction and repair.Remove charge, evacuate and rechargeClean the coil and the filter if necessary, checkthat motors are operating properlyCheck wire guages, etcReplace it

Unit short-cycles

Low refrigerant charge

Insufficient airflow

The compressor runs continuously

The compressor starts but shutsdown quickly on thermal

Thermostat adjustment too high (in heatingmode) or too low (in cooling mode)No fan operation or faulty fanRefrigerant charge too low, leakageHeating/cooling load underestimatedAir or incondensables in refrigerant circuit

Change the setting

Check condenser air circulationFind leak, repair and rechargeReduce load or use next unit size upRemove charge, evacuate and recharge

The Compressor runs too long or continuously

Remove charge,repair,evacuate and recharge

Clean or replace, set the air damper to the rightpositionClean the coilsRemove charge, repair, evacuate and recharge

Insulate them separately

Make sure there are no leaks

Check the air filter, the damper positions.Check that air is not being recycledCheck cleanliness of unit coilsCapillaries obstructed or orifice plugged(humidity)Liquid and gas lines insulated together

Insufficient heating or cooling

Moter windings cut or grounded

Faulty capacitor (single phase models)

Check the wiring and the compressor windingresistanceFind the cause, then replace capacitor

The outdoor fans runs but the compressor will not start

Power failureFuse blown or circuit breaker openVoltage is too lowFaulty contactor, thermostat or relayElectrical connections looseFaulty capacitor (single phase models)Thermostat adjustment too low (in heatingmode) or too high (in cooling mode)Incorrect wiring, terminals loosePressure switch tripped (depending on mode)

Contact the electrical utility companyReplace the fuse or reset the breakerFind the cause and fix itReplace the faulty componentRetighten the connections if necessaryFind the cause, then replace capacitorCheck thermostat setting

Check and retightenFind the cause, then reset

The compressor and outdoor fan do not operate

No heating or cooling

Symptoms Cause Remedy

Note : Open the main unit power switch before proceeding with any repair operations.

1 - General Trouble-shooting Guide

3


Frosted Indoor coilRepair the leak and rechargeCheck the condition of the air filtersCheck the cleanliness of the indoor coilCheck fan motor operationCheck that the air damper opens correctly(on unit equipped with a damper)Install a low temperature kit

Unit noisy

Low refrigerant charge, refrigerant leakInsufficient airflow

Low operating temperature limit exceeded

Make sure vibration isolators have been installed.Check piping collars.

Make sure that the compressor is not losing oilExcessive oil or refrigerant charge

Repair and add oilRepair or replace the thermostat

Tighten any loose components

Electric heat does not work (on indoor units fitted with this option)Thermostat incorrectly adjusted Readjust the thermostat

Remove excess charge

Check continuity througn fuseSafety thermostat opens

Replace faulty elementsCheck indoor unit airflowCheck cleanliness of air filter and coilOpen air balancing dampersIf ducts are long, inhibit low, and perhaps evenmedium fan speedsCheck that wiring complies with applicable diagramsFaultly unit wiring

Excessive or insufficient discharge pressureClean the coilReplace the fan

Remove excess chargeCheck the circuit, evacuate, and recharge

Find and repair the leak, top up refrigerant chargeFind obstructions and eliminate them.Replace the compressor

Out door coil dirtyIndoor unit fan (heating mode) or outdoor unit fan(cooling mode) faultyExcessive refrigerant chargeAir or incondensables in refrigerant circuit

Refrigerant charge too lowLiquid line blocked or crushedCompressor valves worn out or leaking

Refrigerant overchargeCycle changeover valve faulty or leaking (heatpump units)

Remove excess refrigerantReplace the valve

Low refrigreant chargeOutdoor unit coil (heating mode) or indoor unit coil(cooling mode) frostedInsufficient airflow on the outdoor unit coil (heatingmoed) or the indoor unit coil (cooling mode)Suction line obstructedExpansion device obstructed or iced up.Poor contact the line and the defrost sensor in theheating mode (heat pump units)Condenser airflow too high (in the cooling mode)in relation to outdoor air temperature

Add some refrigerantFind cause and fix it

Make sure that the indoor or outdoor unit fan isoperating properlyFind obstruction and eliminateRemove charge, evacuate, rechargeReinstall the sensor correctly using a contactcompound. Insulate the assemblyInstall a low temperature kit

Trouble-shooting Guide (Cont'd) Ice build-up indoor coil

Faulty installtion

Compressor noisy

Safety device

Excessive discharge pressur

Insufficient discharge pressure

Excessive suction pressure

Insufficient suction pressure

Thermostat

4

Excessive or insufficient suction pressure


51. Check before and after troubleshooting

before you start checking or servicing.

1.1. Check power supply wiring. Check that power supply wires are correctly connected to terminals L and N on the terminal plate inthe in door unit.

1-2. Check inter-unit wiring. Check that inter-unit wiring is correctly connected to the outdoor unit from the indoor unit.

1-3. Check power supply. Check that voltage is in specified range (10% of the rating). Check that power is being supplied.

1-4. Check lead wires and connectors in indoor and outdoor units. Check that coating of lead wires is not damaged. Check that lead wires and connectors are firmly connected. Check that wiring is correct.

Electrical Trouble-shooting

WARNINGHazardous voltage can cause ELECTRIC SHOCK orDEATH. Disconnect power or turn off circuit breaker


6 * Set circuit breaker to OFF.

NO

NO

2. Air conditioner does not operate.

2-1. Circuit breaker trips (or fuse blows).A. When the circuit breaker is set to ON, it is tripped soon. (Resetting is not possible.)

There is a possibility of ground fault. Check insulation resistance.If resistance value is 2M or less, insulation is defective (NO).

Remove inter-unit wires from terminal plate in outdoor unit.

Measure insulation resistance of electrical parts in outdoor unit.

Insulation of outdoor unit is defective.

Measure insulation resistance of electrical parts in outdoor unit.

Insulation of indoor unit is defective.

Measure insulation resistance of outdoor unit.

Measure insulation resistance of outdoor unit.

Remove inter-unit wires from terminal plate in outdoor unit. Then, pull the power plug out of the wall outlet


7 Check power supply. Power is being supplied to the indoor unit.

Check capacity of circuit breaker.

Capacity of circuit breaker is suitable.

OPERATION selector switch is set in ON position.

Set OPERATION selector switch to ON.

B. Check " OPERATION selector " switch in the indoor unit.

2-2. Neither indoor nor outdoor unit runs.

A. Power is not supplied.

Measure resistance of compressor motor winding.

Measure resistance of outdoor fan motor winding.

B. Circuit breaker trips in several minutes after turning the air conditioner on. There is a possibility of short circuit.

Replace with suitable one (larger capacity).

NO

Reset breaker. Circuit breaker is tripped.

Wait for recovery or contact power company.

Power failure

YES

NO

Indoor PCB Ass'y is defective

See diagnostics


8 Clean transmitter.

E. Check fuse on the indoor PCB Ass'y.

Check for residue buildup on remote control receiver on front of indoor unit.

Check fuse on indoor PCB Ass' y for continuity. (F)

Check operation lamp to see if light is ON.

Check for residue buildup on transmitter of remote control unit.

D. Check remote control unit.

Try to run with another remote control unit.

First remote control unit is defective.

Clean receiver.

Replace the fuse.

Indoor PCB Ass'y is defective.

Timer is turned ON. Check to see if start or stop is displayed on remote control

F. Check TIMER on the remote control unit.

Cancel the timer mode.

OK

OK

OK

YES

If fuse has been blown,


B. Check power relay in outdoor unit.

9

2-3. Only outdoor unit does not run.

A. Check setting temperature.

Check indoor PCB Ass'y.

Is room temperature too low ?

Remote control unit is defective.

Try to run using another remote control unit.

Try to lower setting temperature by temperature setting button ( button).

Measure coil resistance of power relay. (PR)

NO

OK

Outdoor unit stilldoes not run.

OK


10

Check fan rotation. Tum fan gently once or twice by hand.

Check fan motor capacitor.

Measure resistance of outdoor fan motor winding.

Check fan motor capacitor.

3. Some part of air conditioner does not operate.

3-1. Only indoor fan does not run.

Measure resistance of indoor fan motor winding.

O K

3-2. Only indoor fan does not run.

Check fan rotation. Tum fan gently once or twice by hand.

Repair or replace.

Remove foreignmatter or repair.

OK

Check fan casing foreign matter on inside.

Fan motor burnout or foreign matter in bearings.

Fan cannotbe turned.

Check fan casing foreign matter on inside.

Fan motor burnout or foreign matter in bearings.

Repair or replace.

Remove foreignmatter or repair.

Fan cannotbe turned.


11

Check compressor motor capacitor.

Overload relay is working. (Either OLR T or OLR A)

Temperature of compressor is abnormally high.

Rotor may be locked up.

Refrigerant gas shortage.

3-4. Only flap motor does not run.

3-3. Only Compressor does not run.

Charge refrigerant gas (R22).

Measure resistance of power relay.

Messure Power supply voltage. The voltage is too low.

Measure resistance of compressor motor winding.

YES

YESYES

NONO

Measure resistance of flap motor winding.


12

4. Air conditioner operate, but abnormalities are observed.4-1. Poor cooling.

Insulate both wide and narrow tubes separately and then tape together.

Measure temperature of suction and discharge air of air conditioner.

Charge refrigerant gas (R22).

Possibility of gas shortage.

Temperature difference is small.

Temperature difference between suction and discharge air is large enough (approx. 10 deg. or more

Check for clogging of air filter.

Fan speed is set to LOW.

Clean filter.

Set fan speed to either HIGH or MEDIUM.

Review cooling load estimate, if performance of air conditioner is normal.

Reduce cooling load or replace the air conditioner with larger capacity unit.

4-2. Excessive cooling.

Set temperature is suitable.

Set temperature to higher value using temperature setting buttons of the remote control unit.

NO

YES

NO

YES

Air filter is clogged.

Wide and narrow tubes betweenindoor unit and outdoor unit areinsulated


13

1-1. Power Supply Wires

Clamp the grounding terminal of the power plug with a lead clip of the insulation resistance tester and meaure the resistance by placing a probe on either of the two power terminals. (Fig. 1)

Then, also measure the resistance between the grounding and other power terminals. Fig. 1)

1-2. Indoor Unit

Clamp an aluminum plate fin or copper tube with the lead clip of the insulation resistance tester and measure the resistance by placing a probe on each terminal screw except where the ground line is connected on the terminal plate. (Fig. 2)

1-3. Outdoor Unit

Clamp a metallic part of the unit with the lead clip of the insulation resistance tester and measure the resistance by placing a probe on each terminal screw where power supply lines are connected on the terminal plate. (Fig. 2)

1-4. Measurement of Insulation Resistance for Electrical Parts

Disconnect the lead wires of the desired electric part from terminal plate, capacitor, etc. Similarly disconnect the connector. Then measure the insulation resistance. (Figs. 3 and 4)

NOTE

Refer to Electric Wiring Diagram.

If the probe cannot enter the poles because the hole is too narrow then use a probe with a thinner pin.

NOTE

The shape of the power plug may differ from that of the air conditioner which you are servicing.

Fig.1

Fig.2

Fig.3

Fig.4

1. Measurement of Insulation Resistance

The insulation is in good condition if the resistance exceeds 2M .

CHECKING ELECTRICAL COMPONENTS


14

2. Checking continuity of Fuse On PCB Ass'y

Remove the PCB Ass'y from the electrical Component box. Then pull out the fuse from the PCB Ass'y. (Fig. 5)

Check for continuity using a multimeter as shown in Fig. 6.

3. Checking Motor Capacitor

Remove the lead wires from the capacitor terminals, and then place a probe on the capacitor terminals as shown in Fig. 7. Observe the deflection of the pointer, setting the resistance measuring range of the multimeter to the maximum value.

The capacitor is "good" if the pointer bounces to a great extent and then gradually returns to its original position.

The range of deflection and deflection time differ according to the capacity of the capacitor.

Fig.5

Fig.6

Fig.7


15


16

SYSTEM TEST AND DIAGNOSTICS

TEST OPERATION MODE 1) This is a diagnostic mode to check the functioning of a unit. In installations with multiple units it is possible to start the Test Operation Mode in all of the units sequentially and run the test mode in parallel, thus shortening the time for service calls. By consulting the status of each unit a diagnosis can be made of any problems or normal operation can be verified.

2) Test Operation mode carries out the following operational sequence and then returns to stop operation in normal mode after the Test operation is finished. In the case of Cool only systems the sequence will be completed after STEP 2. If a problem is encountered during Test Operation mode then the unit will indicate this as shown in the chart below and the LED Display will flash according to the LED Diagnotic Codes.

3) To start this mode, the emergency switch must be pressed for at least 10 seconds while in normal operating mode. To interrupt this mode, press the emergency switch again for at least 10 seconds.


Test Operation Mode

In cool only mode Input Operation timeSTEP1 Cool mode, Fan LO Cool mode, Fan LO 7 minutes

Any timer settings entered before the start of the Test Operation Mode will not affected bythe Test operation Mode.

Failure display follows the conditions below.

Status Operation Terminating condition Low HP temp < 18C fan stop and louver full open Coil temp 20C Coil temp >40C(cooling) fan stop and louver full open Coil temp 38C Overheat 65C(heating) louver full open Coil temp 50C Anti Freeze louver full open Coil temp 5C Low voltage halt return to normal range Sensor fail stop system reset Cooling fail stop system reset Heating fail stop system reset

DIAGNOSTIC INFORMATION FUNCTION

1) The control is equipped with a diagnostic information system to report operation of the unit as well as operational failures.

2) These are reported via different flashing patterns of the 3 indicator lights on the unit. The chart below shows the light patterns for the various operational, protrction and failure modes.

3) This feature is intended to provide information to the consumer as well as for service of the units.

17

MinutesStep 1 Fan only high 3Step 2 Cool mode : fan high 4 Diagnostic

Cool mode : fan med 2Cool mode : fan low 3

Step 3 Stop Waiting 3Heating mode : fan high 4 Diagnostic

Step 4 Heating mode : fan med 2Heating mode : fan low 3

Step 5 Wait 3


Status Power Timer Operation Mode

OFF(with power on)ON (Temperature satisfied)Waiting for delayCompressor startedSleep modeStart timer setStop timer setLow HP temp < 18CCoil temp > 40C (cooling)Overheat > 62 (heating)Anti FreezeLow voltageSensor failCooling failHeating failEmergency operationTest operationFilter

OO

F-1OX

F-2F-3OO

F-1F-2OOOO

Note 1F-1F-3

OXXXXXXXXXX

F-2F-1F-2F-3F-3F-1

F-3

OOOX

X/OX/OX/OF-1F-2F-1F-2O

F-1F-2F-3

Note 1F-1F-3

Normal OperationNormal OperationNormal OperationNormal OperationNormal OperationNormal OperationNormal Operation

Protection ProtectionProtectionProtectionProtection

Reset-Call Service TechnicianReset-Call Service TechnicianReset-Call Service Technician

OperationalOperationalProtection

18

LED DIAGNOSTIC OTPUT CODES

Light Pattem codes X = On, O = OFF F-1 = ON:0.5sec,OFF:0.5sec F-2 = ON:1.0sec,OFF:0.5sec F-3 = ON:0.5sec, OFF:1.sec

Notes1) In emergency mode, the Power ligh will flash and the other lights will indicate the operation as above.2) If the test operation was completed or was interrupted by the user, then the operation of the unit will resume operation in the mode that was selected before the Test Operation Mode was initiated.3) Lights will flash during the time that the units is held off, due to Low Voltage. If the voltage has passed through the reset voltage and the unit is waiting for the time delay, the lights will go to normal operation.4) The lights will show the LED Diagnostic code even when the unit is off.


Name, address and phone number of your contractor :

19


Trouble Shooting Guide York

Documents

Transcript of Trouble Shooting Guide York