Protection Function - Haier AS09/12GS2ERA Service Manual

5.2.5 The outdoor defrosting control
A.The conditions for entering into defrosting mode
When starting running heating, the compressor continuously runs for over 10 minutes, after running
for 45 minutes in all (defrosting is ended or when entering into refrigeration mode, clear the
compressor's cumulative run time), through detecting the defrosting sensor TCS detect the defrosting
situation of the heat exchanger of the outdoor unit and the outdoor environment temperature sensor
TA, and meeting the following conditions continuously for 2 minutes, the machine enters into the
defrosting operation:
TCS C×TA
is determined as the following according to the data of EEPROM:
C selcet if Tao 0
The temperature limitation for entering into defrosting mode -15
B.Defrosting time interval
When the result of C×TA
45 minutes (the time interval which is in 57 digits in EEPROM can be adjusted
When the result of C×TA
defrostings is 65 minutes.
C.Defrosting operation
When starting defrosting, the compressor stops for 1 minute at first, and the outdoor fan is running,
after 55 seconds, the four-way valve is off.
When the compressor is started, the outdoor fan is stoped, the compressor stops for 30 seconds at
the conditions of 58HZ, and then runs towards the target frequency—88HZ.
During defrosting period, the protections, such as current of the compressor, compressor's blowing
and so on, are in effect. During defrosting period, the compressor which is stoped because of
protection or malfunction will reinstate after stoping for 3 minutes, and don't clear the cumulated run
time. When it is satisfied with the continuously running time, it will enter into the defrosting mode.
After entering into defrosting mode, make sure the compressor runs for at least for 2 minutes, and
then it can withdraw from defrosting.
If a single machine causes defrosting, the other machines all involve in defrosting.
D.The conditions of withdrawing from defrosting
The defrosting operation will change to heating operation, if any of the following conditions is satisfied:
1 The temperature of the outdoor heat exchanger is continuously over 7
2 The temperature of the outdoor heat exchanger is continuously over 12
3 Continuously run defrosting for 11 minutes 56 digits in EEPROM can be adjusted .
E When satisfying the conditions of withdrawing from defrosting, the machine works as the
followings:
The compressor stops, the outdoor fan is started, and the four-way valve is closed, after 60 seconds
the compressor runs according to the starting process.

5.2.6 Protection function

5.2.6.1 TTC high temperature-preventing protection
Once the machine is started, it can run TTC overheating protection of air-blowing, but air-blowing
sensor malfunction must alarm after 4 minutes during which the compressor is started (during the
AS09/12GS2ERA 1U09/12BS1ERA-SM
C=0.8;if Tao 0 C=0.6
is in the scope of -15
is in the scope of C×TA
is read from EEPROM Normal State: =6
C×TA
C×TA , the interval between two defrostings is
<-15 , the time interval between two
Domestic Air Conditioner
Function and control
-5
for 80 seconds.
for 5 seconds.