Haier H-MRV Series Service Manual

Also see for H-MRV AB092FCBHA: Service manual User manual

Contents

9.1 According to the temperature measured by Td, the unit will adjust compressor frequency whendischarging temperature is overheat. When spraying refrigerant cannot efficiently decreasedischarging temperature, the system will make decrease-frequency protection.9.2 When Td is over 110℃, the frequency will reduce 10Hz for every 120 seconds. When the outputfrequency has become the low limit, Td is still over 110℃, the unit will stop.10. Oil return operation10.1 Oil return operation in coolingEntering condition:Indoor thermostat OFF time is over 30 minutes (after oil return operation, time again frombeginning).In cooling mode, compressor runs for 1 hour in all (after oil return operation, time again frombeginning).Operation procedure:After oil return signal has been sent to indoor for 30 seconds, the unit will begin oil return operation.Compressor running frequency is the oil return frequency, outdoor EEV open angle does notchange and quit oil return 4 minutes later, then resume the frequency before oil return operation,finally, send oil return finish signal to indoor unit.10.2 Oil return operation in heatingEntering condition:Indoor thermostat OFF time is over 30 minutes (after oil return operation, time again frombeginning).In heating mode, compressor runs for 1 hour in all (after oil return operation, time again frombeginning).Operation procedure:After oil return signal has been sent to indoor for 30 seconds, the unit will begin oil return operation.Compressor running frequency is the oil return frequency, outdoor EEV open angle is the specialangle for heating oil return and quit oil return 4 minutes later, then resume the corresponding baseangle due to the indoor capacity.11. Compressor overheat protectionValues saved in EEPROM:Parameter Current protection data unit Data out of factory Actual dataOver current protection Over_c (Pr-24) % 130 13*130%=16.9(A)Over load protection Ov_load (Pr-23) % 106 13*100%=13(A)Overcurrent stallprotection Oc_stall (Pr-26) % 96 13*88%=11.5(A)Overload fixedfrequency protectionvalueOv_load2 (Pr-28) % 100 13*96%=12.5 (A)Rated current Rate_c (Pr-20) A 13 13(A)12. Input protection signalHigh/low pressure switch protection:When input of pressure switch is 0, that shows no protection.When input of pressure switch is 1 for 1 minute, that shows high pressure protection, andcompressor stops, then there will be failure alarm signal. If alarm has been solved, the protection -103-