Air Conditioner Service Manual
4
3.
Operation details
Electronic Controller
1.
Safety Protection
(1)
Time Delay for Safety protection
⚫
3 minutes delay for compressor ---The compressor is ceased for 3minutes before restarting
to balance the pressure in the refrigeration cycle in order to protect the compressor.
⚫
150 seconds delay for 4-way valve---The 4-way valve will be ceased for 150 seconds
late after compressor to prevent the refrigerant-gas abnormal noise when the HEATING
operation is OFF or switch to the other operation mode.
(2)
Discharge temperature protection
There is a temperature sensor on discharge pipe, when temperature on discharge pipe
exceeded the limit 115
℃
, system control will shut down the compressor and the display board
will show the error code.
(3)
Lower voltage protection
When AC voltage <160V, DC voltage<170V, unit will be shut down for protection and recover while
the AC voltage ˃170 V, DC voltage ˃190V.
(4)
Over voltage protection
When AC voltage ˃ 275V, DC voltage ˃400V unit will be shut down and recover while AC
voltage<255V, DC voltage<390 V.
(5)
Over current protection
When the current of outdoor unit is overload, controller will drop the operation frequency or shut
down the unit immediately and show error code.
(6)
Condenser temperature protection
When condenser temperature≥ 65
℃
and keep 10s,
the air conditioner will shut down, and
show error code, and recover while condenser temperature<52
℃
and the compressor stop for
3minutes
.
(7)
IPM
module protection
IPM module has high temperature & over current protection itself, if there is signal feedback to
IPM, the outdoor unit will shut down, LED on outdoor PCB will show the error code.
(8)
Evaporator freeze protection.
When evaporator temperature<2
℃
,
the
controller
will drop compressor operate
frequency.
When evaporator temperature<0
℃
and keep 1 minute, the expand valve of the unit will stop.
When all of the operating unit enter freeze protect, the compressor will stop and recover while
evaporator temperature and stop for 3 minutes.
2.
“Feel” Mode Operation
1. The set temperature can be adjusted from 16-31
℃
on auto mode, the operation of fan speed and
vane position according to preset.
2. Operation
When unit set to auto mode, it will work on cooling, heating or fan mode totally according to Δt --the
temperature difference between RT and ST shown as table:
Mode
Δt=RT-ST
COOLING
Δt >1
℃
FAN
-1
℃
≤Δt≤ 1
℃
HEATING
Δt <-1
℃
3. “COOLING” Mode Operation
(1)
Compressor frequency control
According to difference room temperature and set temperature (
δt = RT-ST
), running frequency