Haier AW07EH2VHA, Service Manual

Page: 138 / 140

TROUBLESHOOTING & REFERENCES
J-26
ENGLISH
Topic Title Flow Charts
Power on
Short the high pressure
switch terminal on the PCB.
Does the system report a
failure?
Is the fan motor is ok?
Is the resistance of Te and
Tc within range?
The PCB is bad,
replace it.
Replace
sensor
No
Yes
Yes
No
No
Replace the fan
motor
[42] Open high pressure switch
High pressure switch: Switch circuit has been detected open for
30 seconds (after 3 minute of compressor run time). Error locks
if it occurs 3 times in 1 hour.
Possible causes:
• Incorrect pressure switch wiring
• Abnormal system pressure
• System is clogged
• Incorrect refrigerant charge
• Bad valve
• Pressure switch is bad
• PCB is bad
Reconnect
Power off. Is pressure switch
wiring connection ok?
Use multimeter to check the high
pressure switch. Is the switch
short circuited?
Is the EEV coil wiring correct and
firmly in place?
Is the stop valve is open?
Use a multimeter to check
the resistance of Tc & Tm.
Are they withing range?
Is the piping system clogged?
Is the connection pipe bent?
The pressure is bad,
replace it.
Open the stop valve
Clean the piping system
Replace the connection
pipe
Replace the
sensor
Yes
Yes
No
Yes
Yes
No
No
No
No
No
Yes
No
No
Reconnect the EEV
coil wiring
[43] Open low pressure switch
Low pressure switch: Switch has been detected open
for 60 seconds (after 3 minute of compressor run
time) or open for 30 seconds during standby.
Possible causes:
• Incorrect pressure switch wiring
• Abnormal system pressure
• System is clogged
• Incorrect refrigerant charge
• Bad valve
• Pressure switch is bad
• PCB is bad