SANG TAC-12CHSA/JAI, Service Manual

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Air Conditioner Service Manual
maximum adjustment is RT±2
℃
.
4.
3 Cooling Mode
(1) Compressor frequency control.
According to the difference of Room Temperature and Set Temperature (
δt = RT-ST
), running
frequency of the compressor is controlled by electronic controller. When room temperature is
much higher than set temperature, the compressor will start at a high frequency, and while the
room temperature goes down, the compressor running frequency decline to lower value.
When room temperature is lower than the set target, the compressor will run at very low frequency.
In general, unit will change its running frequency according to
δt
to make the room temperature
closing to the set value.
(2) Outdoor temperature affects running frequency of the compressor.
Outdoor temperature affect
compressor’s running frequency. Difference inlet temperature of
outdoor unit is adapted by difference compressor running frequency. While outdoor temperature is
about 30
℃
, the compressor will run in high frequency.
If unit run in
“Cooling” mode and outdoor temperature is less than -2 ℃
,the controller will shut down
compressor and show error code, while the ambient temperature is over 1
℃
, the compressor will
run automatically.
(3) Auto fan control in cooling mode.
In cooling mode ( include cooling at FEEL mode ), fan speed is determined by
δt
as the
following diagram:
(4) Anti-frosting protection of indoor evaporator.
If
IPT≤-1°C detected in consecutive 3 min, the compressor and outdoor fan motor stop operation,
indoor fan motor runs at preset speed; I f
IPT≥5°C detected 3min later, then outdoor fan motor and
compressor will start up again, and
indoor fan motor restores to it’s original state.
(5) ODU overheating protection.
If OPT>105°C, the compressor stop operation for protection.
If O
PT≤90°C, the air conditioner recover to operate.
RT-ST
4℃
2℃
0℃
δt come down
δt come up
High fan
Mid fan
Low fan
4℃
2℃