
TCL Air Conditioner Service Manual
12
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.
4.1.3 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.
4.1.4 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.
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.