Haier HSU12XHK Service Manual page 16

*Current protection and current expiration protection: (Not detecting within 60 seconds after start up)
*Overcooling protection One and half a minutes later after compressor starts, if the temperature of coil
pipe is below 2°F, compressor and air outlet stop, and air inlet runs according to the temp. setting.
Compressor can be restarted 3 minutes later.
5.1.5.3 Defrosting:
5.1.5.3.1 Entry conditions of defrosting:
The entry conditions of defrosting is classified into two types: intelligent
defrosting. Through selecting and judging, the models without outdoor sensor defrosts according to
intelligented defrosting, and others with ensor defrosts according to sensor defrosting.
Intelligented defrosting:
5.1.5.3.1.1 Indoor unit enter overload protection and air outlet stops when air outlet has been restarted
and runs over 10 minutes, and compressor runs over 45 minutes in total and over 20 minutes continuously,
and the temp. of indoor coil pipe is below 100°F.
5.1.5.3.1.2 Compressor runs 20minutes continuously, and the temp. of indoor coil pipe decreases 2°F
per 6 minutes and this operation repeats 3 times, and the temp. of coil pipe is below 100°F, and 5 minutes
later after compressor is restarted.
5.1.5.3.1.3 When compressor runs over 3 hours in total and over 20 minutes continuously and after
the temp. of indoor coil pipe is below 100°F, the system enters defrosting mode.
5.1.5.3.1.4 The difference between the temp. of indoor coil pipe and the indoot temp. is below 60°F and
lasts 5 minutes, compressor runs over 45 minutes in total and over 20 minutes continuously after the temp. of
indoor coil pipe is below 100°F, the system enters defrosting mode.
5.1.5.3.2 Exit conditions of defrosting:
Defrosting time is higher than 12 minutes (compressor is on).
5.1.5.3.2.1 During the defrosting, if current peak value is cut off, the unit quit the defrosting mode. But
the protection of expiration of current peak value is unavailable with 60 senconds after compressor is started.
5.1.5.3.2.2 During the defrosting and 2 minutes After quiting the defrosting mode, abnormality of temp.
sensor isn't detected.
5.1.5.3.2.3 After quiting the defrosting mode, the fan motor enter cooling prevention mode.
5.1.5 Timer function:
You can set 24-hour timer on or timer off as required, and the minum time unit is 1 minute. After setting,
HSU09/12XHK
13
Functions and Control
defrosting and sensor
Domestic Air Conditioner