3
7
Installation and Maintenance
Service Manual
Possible Causes
Discriminating Method (Air conditioner Status)
Troubleshooting
Set temperature is improper
Observe the set temperature on remote controller Adjust the set temperature
Rotation speed of the IDU fan
motor is set too low
Small wind blow
Set the fan speed at high or medium
Filter of indoor unit is blocked
Check the filter to see it's blocked
Clean the filter
Installation position for indoor unit
and outdoor unit is improper
Check whether the installation postion is proper
according to installation requirement for air
conditioner
Adjust the installation position, and install the
rainproof and sunproof for outdoor unit
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 4-way valve
Blow cold wind during heating
Replace the 4-way valve
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
Flow volume of valve is
insufficient
The pressure of valves is much lower than that
stated in the specification
Open the valve completely
Malfunction of horizontal louver Horizontal louver can’t swing
Refer to point 3 of maintenance method for
details
Malfunction of the IDU fan motor The IDU fan motor can’t operate
Refer to troubleshooting for H6 for maintenance
method in details
Malfunction of the ODU fan motor The ODU 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
9.3 Maintenance Method for Normal Malfunction
1. Air Conditioner Can't be Started Up
2. Poor Cooling (Heating) for Air Conditioner
3. Horizontal Louver Can't Swing
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.
Wrong wire connection between
indoor unit and outdoor unit,
or 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
Make sure the air conditioner is grounded
reliably
Make sure wires of air conditioner is connected
correctly
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
Possible Causes
Discriminating Method (Air conditioner Status)
Troubleshooting
Wrong wire connection, or poor
connection
Check the wiring status according to circuit
diagram
Connect wires according to wiring diagram to
make sure all wiring terminals are connected
firmly
Stepping motor is damaged
Stepping motor can't operate
Repair or replace stepping motor
Main board is damaged
Others are all normal, while horizontal louver
can't operate
Replace the main board with the same model
