TGM YAP1FF - Page 72

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Installation and Maintenance
Service Manual
9. Maintenance
Analysis or processing of some of the malfunction display:
1. Compressor discharge protection
Possible causes: shortage of refrigerant; blockage of air lter; poor ventilation or air ow short pass for condenser; the sys-
tem has noncondensing gas (such as air, water etc.); blockage of capillary assy (including lter); leakage inside four-way
valve causes incorrect operation; malfunction of compressor; malfunction of protection relay; malfunction of discharge sen-
sor; outdoor temperature too high.
Processing method: refer to the malfunction analysis in the above section.
2. Low voltage overcurrent protection
Possible cause: Sudden drop of supply voltage.
3.Communication malfunction
Processing method: Check if communication signal cable is connected reliably.
4. Sensor open or short circuit
Processing method: Check whether sensor is normal, connected with the corre sponding position on the controller and if
damage of lead wire is found.
5. Compressor over load protection
Possible causes: insufcient or too much refrigrant; blockage of capillary and increase of suction temp.; improper running of
compressor, burning in or stuck of bearing, damage of discharge valve; malfunction of protector.
Processing method: adjust refrigerant amount; replace the capillary; replace the compressor; use universal meter to check if
the contactor of compress or is ne when it is not overheated, if not replace the protector.
6. System malfunction
i.e.overload protection.When tube temperature(Check the temperature of outdoor heat exchanger when cooling and check
the temperatur e of indoor heat exchanger when heating) is too high, protection will be activated.
Possible causes: Outdoor temperature is too high when cooling; insufcient outdoor air circulation; refrigerant ow malfunc-
tion.
please refer to the malfunction analysis in the previous section for handling method .
7. IPM module protection
Processing method:Once the module malfunction happens,if it persists for a long time and can not be selfcanceled, cut off
the power and turn off the unit,and then re-energize the unit again after about 10 min.After repeating the procedure for sever
times, if the malfunction still exists,replace the module.
Error
code
Malfunction name AC status Possible causes
Malfunction of zero-
crossing signal of indoor
unit
Compressor, outdoor fan and
indoor fan stop operation.
1. The power is abnormal;
2. Main board of indoor unit is damaged.
Zero-crossing malfunction
of outdoor unit
Cool: compressor stops
operation, while indoor fan
operates; Heat: all loads stops
operation.
Replace the control board of outdoor unit.
Evaporator anti-freezing
protection
Not error code, it is the status code in cooling process
Anti cold air protection Not error code, it is the status code in cooling process
Heat
indicator
Flash
once/
10s
Defrosting Not error code, it is the status code in cooling process