Haier Unitary smart series Service Manual page 177

12) Outdoor low pressure abnormal
Outdoor indicator shows 11000.
Alarm condition: outdoor system pressure is lower than 0.05MPa.
outdoor indicator shows 11000
measure actual pressure by a
pressure gauge to adjust the
output failure
yes
low pressure
abnormal
check if high
pressure is low,too
yes
Lack of refrigerant, charge
additional refrigerant and check if
piping leaks, if yes, replace piping
Indoor troubleshooting:
1) Sensor failure
Alarm condition: ambient temperature sensor is in short
circuit or open circuit for 2 seconds continously.
check if the wiring is
correct according to
wiring diagram
if sensor is fixed
well
yes
Is sensor resistance
acceptable?
yes
Is sensor short-circuit
or open-circuit?
no
Replace PCB
no
replace pressure
switch
no
check if piping is blocked
no
reconnect
no
Relocate
no
Replace sensor
yes
Replace sensor
a__
yes
dredge piping
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