Haier HSU-07HV03/R2 Service Manual page 54

off.(different mode has the different CT value)
Overcooling protection:
One and a half minute later after compressor starts, if the temperature of coil pipe is
below -4¡æ, compressor and air outlet stop, and air inlet runs according to the temp.
setting. Compressor can be restarted 3 minutes later.
Defrosting:
1.Entry conditions of defrosting:
A. 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 38
¡æ.
B. Compressor runs 20 minutes continuously, and the temp. of indoor coil pipe
decreases 1¡æ per 6 minutes and this operation repeats 3 times, and the temp. of
coil pipe is below 38¡æ, then 5 minutes later . the system enters defrosting mode.
C. When compressor runs over 3 hours in total and over 20 minutes continuously
and after the temp. of indoor coil pipe is below 38¡æ, the system enters defrosting
mode.
D. The difference between the temp. of indoor coil pipe and the indoot temp. is
below 18¡æ and lasts 5 minutes, compressor runs over 45 minutes in total and
over 20 minutes continuously, the temp. of indoor coil pipe is below 38¡æ, the
system enters defrosting mode.
2.Exit conditions of defrosting:
Defrosting time is higher than 12 minutes (compressor is on), or CT current is above
(CT1).
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.
During the defrosting and 2 minutes after the defrosting, abnormality of temp.
sensor isn't detected.
After quiting the defrosting mode, the fan motor enter cooling prevention mode.
3.Defrosting oscillogram:
Air Conditioner
Edition:2006/1/10