Carrier 619FB Service Manual page 44

TROUBLESHOOTING FOR NORMAL MALFUNCTION
1. Air conditioner can not start up
Possible Causes
No power supply or poor connection for power plug
Wrong wire connection between indoor unit and the
outdoor unit, or poor connection for wiring
terminals.
Electric leakage from air conditioner
Model selection for air switch is improper
Malfunction of remote controller
2. Poor cooling (heating) for air conditioner
Possible Causes
Set temperature is improper
Rotation speed of the IDU fan motor is set too low
Filter of indoor unit is blocked
Installation position for the indoor and outdoor units
is improper
Refrigerant is leaking
Malfunction of 4- - way valve
Malfunction of capillary
Flow volume is insufficient
Malfunction of horizontal louver
Malfunction of the IDU fan motor
Malfunction of the ODU fan motor
Malfunction of compressor
3. Horizontal louver can not swing
Possible Causes
Wrong wire connection, or poor connection
Stepping motor is damaged
Main board is damaged
Discriminating Method
(Air Conditioner Status)
After energizer, operation indicator is not bright and
the buzzer can not give out sound.
Under normal power supply circumstances,
operation indicator is not bright after energization
After energization, room circuit breaker trips off at
once.
After energization air switch trips off
After energization, operation indicator is bright while
no display on remote controller or buttons have no
action.
Discriminating Method
(Air Conditioner Status)
Observe the set temperature on remote controller
Small wind blow
Check the filter to see if its blocked
Check whether the installation position is correct
according to installation requirements for air
conditioner.
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.
Blow cold wind during heating
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. If
refrigerant is not leaking, part of capillary is blocked.
The pressure of valves is much lower than that
stated in the specification
Horizontal louver can not swing
The IDU fan motor can not operate
The ODU fan motor can not operate
Compressor can not operate
Discriminating Method
(Air Conditioner Status)
Check the wiring status according to the circuit
diagram
Stepping motor cannot operate
Others are all normal while horizontal lover can not
operate
44
Troubleshooting
Confirm whether it's due to power failure. If yes,
wait for power recovery. If not, check power supply
circuit and ensure the power plug is connected well.
Check the circuit according to the circuit diagram
and connect wires correctly. Ensure all wiring
terminals are connected firmly.
Ensure the air conditioner is ground reliably. Ensure
wires of the air conditioner are connected correctly.
Check the wiring inside the air conditioners. Check
whether the insulation layer of power cord is
damaged; if yes replace the power cord.
Select proper air switch
Replace batters for remote controller Repair or
replace remote controller
Troubleshooting
Adjust the set temperature
Set the fan speed at high or medium
Clean the filter
Adjust the installation position and install the
rainproof and sun proof for the outdoor unit
Find the leakage causes and repair them. Add
refrigerant.
Replace the 4- - way valve
Replace the capillary
Open the valve completely
Refer to point 3 of maintenance method for details
Refer to troubleshooting for H6 for maintenance
method in details
Refer to point 4 of maintenance method for details
Refer to point 5 of maintenance method for details
Troubleshooting
Connect wires according to the wiring diagram to
ensure all wiring terminals are connected firmly
Repair or replace stepping motor
Replace the main board with the same model