Air Conditioner Service Manual
16
delay for the motor should be less than 160s.
2). When switch on unit on cooling mode, ODU fan motor will delay 5s after compressor starts up.
4. When ODU failure or stops for protection, IDU works as preset.
5.
Anti-frosting protection
Control the unit operation frequency and the frequency changing rate to achieve anti-frosting protection.
1). Frequency Slowly Increasing(FSI):
a. If 6
℃
≤IPT
＜
7
℃
, the frequency increasing rate is 1Hz/60s, slowly increasing operation speed.
b. When IPT≥7
℃
, unit quit from protection.
2). Frequency Limitation:
If 5
℃
≤IPT
＜
6
℃
, the compressor frequency forbidden to increase
3). Normal Frequency Decreasing (NFD):
If 3
℃
≤IPT
＜
4
℃
, the frequency decreasing rate is 8Hz/90s, until to the lower frequency limit.
4). Fast Frequency Decreasing (FFD):
If 2
℃
≤IPT
＜
3
℃
, the frequency decreasing rate is 16Hz/90s, until to the lower frequency limit.
5). Unit stop:
a. When IPT
＜
1
℃
for 3min continuously, unit stops working for anti-defrosting protection.
b. While IPT
＞
6
℃
, and the unit stopped for 3 min already, can the unit recover to operation.
0
℃
-1
℃
-2
℃
-3
℃
RT-ST
COMPRESSOR
OUTDOOR FAN
INDOOR FAN
160S
160S
10min.
5min.
2min.
ON
OFF
5s
0.5
℃
≥ 7min.
≥3min.
6.2.3 Dry mode
1. Temperature control: 16~31
℃
.
Fan speed: low
Vane blade position: as customer preset
2. When ODU failure or stops for protection, IDU works as preset.
3. Failure protection: as cooling mode.
4. Energy saving and sleep mode: Invalid.
6.2.4 Heating mode
1. Temperature control:
16-31
℃
.
2. Compressor and process control.
1). When ST-CRT≥0.5
℃
, the compressor starts up working, AC operates as customer preset;;
2). When
a. ST-CRT≤
－
3
℃
and compressor keeps 2 min continuously; or
b. ST-CRT≤
－
2
℃
and compressor works in lowest frequency for 5 min continuously; or
c. RT-CRT≤
－
1
℃
and compressor works in lowest frequency for 10 min continuously,
The compressor stops operation.
3). The compressor frequency control: Based on relation of RT & ST, and the changing speed of RT.
