Air Conditioner Service Manual
18
3). The compressor frequency control: Based on relation of RT & ST, and the changing speed of RT.
4). The compressor will also stop working while unit:
a. switched off.
b. under protection.
c. changed to fan mode.
5). Under normal operation, the compressor can be stopped by program only working after 7 min once it starts up.
6). In the process of unit operation, once the compressor ceased, it should be 3 min delay for the next procedure.
3. IDU time delay:
When compressor stops or unit switches off while in heating mode, IDU fan motor will work for a
few seconds more to prevent overheat.
4: ODU Fan motor control:
1). While unit:
a. To be switched off
b. Under protection.
c. To the set temperature
After compressor ceased, the fan motor stops working according to the temperature of OPT and OAT, the max
delay for the motor should be less than 160s.
2). When switch on unit on heating mode, ODU fan motor will delay 5s after compressor starts up
3). in the process of defrosting, the fan motor will stop operation 48s delay after compressor stopped.
4). defrosting finish, the compressor stops operation, the fan motor will start working simultaneously.
5. 4-way valve control
1). On Cooling/Dry/Fan mode,4-way valve:
OFF,
when unit switched on heating mode,4-way valve:
ON.
2). When heating mode switched off, or changed from heating to other modes, the 4-way valve will be
OFF
2 min
delay after the compressor stops working.
3). Unit stops working caused by any kind of protection, the 4-way valve will be
OFF
4 min delay.
4). In the process of defrosting, 4-way valve will be
OFF
43s delay after compressor stopped.
5). When defrosting finish, the compressor stops operation, 4-way valve will be
ON
after 43s delay.
0
℃
-1
℃
-2
℃
-3
℃
ST-CRT
COMPRESSOR
OUTDOOR FAN
INDOOR FAN
2 min.
10 min.
5min.
≥ 7min.
160S
160S
≥3min.
4-way VALVE
5s
ON
OFF
0.5
℃
≤2min.
≤2min.
