Haier AB25S2SC1FA, Service Manual

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· When unit stops, the reason that system still checks the low pressure : in a long time stop, make
protection for the compressor on the condi tion of great refrigerant leakage.
· The reason that low pressure switch action time is 30 seconds: when compressor stops, low pressure
does not change, so it will be shorter than the set time in operation.
(3) When compressor starts up, in 8 minutes, low pressure switch signal will be shielded.
(4) In defrosting, low pressure switch will be shielded.
(5) In oil return procedure, low pr essure switch will be shielded.
(6) In the refrigerant discharging procedure after the oil return in cooling is over, low pressure switch will
be shielded.
In addition, the system will control low pressure through the evaporator temp. TE to realize the low
pressure protection function.
In cooling, confirm through Tc2AVE:
In heating, confirm through defrosting temp. Te:
If the failure is not confirmed as the permanent protection, outdoor will not send failure code to indoor, and
indoor will not alarm.
Tin
AVE
-25
℃
-30
℃
-35
℃
-40
℃
-45
℃
Normal operation
Min. running FQY 20HZ
SV2 OFF & 20HZ
SV2 ON & 20HZ
Keep for 5 seconds, unit stops and alarm
occurs. 3 minutes later, restart up. If it
occurs 3 times in 1 hour, it will always
alarm and stop, electrify again and failure
will be cleared.
Te -30
℃
-35
℃
-40
℃
-45
℃
-50
℃
Normal operation
Min. running FQY 20HZ
SV2 OFF & 20HZ
SV2 ON & 20HZ
Keep for 5 seconds, unit stops and
alarm occurs. 3 minutes later, restart
up. If it occurs 3 times in 1 hour, it will
always alarm and stop, electrify again
and failure will be cleared.