Service Manual
Installation and Maintenance
35
9.3 Maintenance Method for Normal Malfunction
1. Air Conditioner Can't be Started Up
Possible Causes
Discriminating Method (Air conditioner Status)
Troubleshooting
No power supply, or poor
connection for power plug
After energization, operation indicator isn’t bright
and the buzzer can't give out sound
Confirm whether it's due to power failure. If yes,
wait for power recovery. If not, check power
supply circuit and make sure the power plug is
connected well.
Poor connection for wiring
terminals
Under normal power supply circumstances,
operation indicator isn't bright after energization
Check the circuit according to circuit diagram
and connect wires correctly. Make sure all
wiring terminals are connected firmly.
Electric leakage for air conditionerAfter energization, room circuit breaker trips off at
once
1.Make sure the air conditioner is grounded
reliably.
2.Make sure wires of air conditioner is
connected correctly.
3.Check the wiring inside air conditioner. Check
whether the insulation layer of power cord is
damaged; if yes, place the power cord.
Model selection for air switch is
improper
After energization, air switch trips off
Select proper air switch
Malfunction of remote controller
After energization, operation indicator is bright,
while no display on remote controller or buttons
have no action.
1.Replace batteries for remote controller.
2.Repair or replace remote controller.
2.Poor Cooling for Air Conditioner
Possible Causes
Discriminating Method (Air conditioner Status)
Troubleshooting
Set temperature is improper
Observe the set temperature on remote controller
or Membrane
Adjust the set temperature.
Rotation speed is set too low
Small wind blow
Set the fan speed at high or medium.
Filter is blocked
Check the filter to see it's blocked
Clean the filter.
Installation position for unit is
improper
Check whether the installation postion is proper
according to installation requirement for air
conditioner
Adjust the installation position.
Refrigerant is leaking
Discharged air temperature during cooling is
higher than normal discharged wind temperature;
Discharged air temperature during heating is
lower than normal discharged wind temperature;
Unit's pressure is much lower than regulated
range
Find out the leakage causes and deal with it.
Add refrigerant.
Malfunction of capillary
Discharged air temperature during cooling is
higher than normal discharged wind temperature;
Discharged air temperature during heating is
lower than normal discharged wind temperature;
Unit't pressure is much lower than regulated
range. If refrigerant isn’t leaking, part of capillary
is blocked
Replace the capillary.
Malfunction of fan motor
The fan motor can’t operate
Refer to point 4 of maintenance method for
details.
Malfunction of compressor
Compressor can't operate
Refer to point 5 of maintenance method for
details.
3.Poor Heating for Electric Heater
Possible Causes
Discriminating Method (Air conditioner Status)
Troubleshooting
Electric heating relay on main
board is damaged
Even heating condition is satisfied, electric heater
can’t be started up under heating mode
Replace the main board with the same model.
Connection needle stand between
main board and display board is
loose
Even heating condition is satisfied, electric heater
can’t be started up under heating mode
Insert the needle stand tightly.
Set temperature and ambient
temperature are almost the same
Poor heating effect
Increase the set temperature.
