Fedders GWH18MC-D3DNA1A/O, Service Manual

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29
Function and Control
5. Power turn-off:
If the T
Cooling overload power turn-off temperature
≤T
outer pipe
, then Cooling overload protects machine stopping; If T
outer
pipe
T
Cooling overload frequency-limited temperature
and the compressor has been stopped working for 3 minutes, the
machine should be allowed to operate.
6. If the Cooling overload protection power turn-off continuously occurs for six times, it should not be resumed
automatically, and you should press the ON/OFF button to resume if the fault keeps on. During the process of
running, if the running time of compressor exceeds the t
overload protection times zero clearing time
, the times of overload
protection power turn-off should be cleared to recount. The mode of stopping the machine or transferring to
supply air will clear the trouble times immediately (if the trouble can not be resumed, transferring mode will not
clear it).
Overload protection function at the mode of heating
Starting estimation :
After the compressor stopped working for 180s, if T
inner pipe
T
heating overload frequency-limited temperature
(the
temperature of hysteresis is 2 ), the machine is allowed to start, otherwise it should not be started, and should
be stopped to treat according to the overload protection:
Clear the trouble at the mode of power turn-off / heating, and the protection times are not counted.
1. Frequency limited
If T
heating overload frequency-limited temperature
≤T
inner pipe
T
heating overload frequency reducing temperature at normal speed
, you should
limit the frequency raising of compressor.
2. Reducing frequency at normal speed and stopping machine:
If T
heating overload frequency reducing temperature at normal speed
≤T
inner pipe
T
heating overload frequency reducing temperature at high speed
,
you should adjust the compressor frequency by reducing 8Hz/90s till the lower limit; After it was running 90s at
the lower limit, if T
heating overload frequency reducing temperature at normal speed
≤T
inner pipe
, then overload protects machine
stopping;
3. Reducing frequency at high speed and power turn-off:
If T
heating overload frequency reducing temperature at high speed
≤T
inner pipe
T
heating overload power turn-off temperature
you should
adjust the compressor frequency by reducing 30Hz/90s till the lower limit; After it was running 90s at the lower
limit, if T
heating overload frequency reducing temperature at normal speed
≤T
outer pipe
, then Cooling overload protects machine
stopping;
4. Power turn-off:
If the T
heating overload power turn-off temperature
≤T
inner pipe
, then overload protects machine stopping; If T
inner pipe
T
heating overload frequency-limited temperature
and the compressor has been stopped working for 3 minutes, the machine
should be allowed to operate.
5. If the overload protection power turn-off continuously occurs for six times, it should not be resumed
automatically, and you should press the ON/OFF button to resume if the fault keeps on. During the process of
running, if the running time of compressor exceeds the t
overload protection times zero clearing time
, the times of overload
protection power turn-off should be cleared to recount. The mode of stopping the machine or transferring to
supply air will clear the trouble times immediately (if the trouble can not be resumed, transferring mode will not
clear it).
Protective function for discharge temperature of compressor
1. Starting estimation:
After the compressor stopped working for 180s, if T
Discharge
T
Discharge limited temperature
(the temperature of
hysteresis is 2 ), the machine is allowed to start, otherwise it should not be started, and should be stopped to
treat according to the discharge temperature:
The machine should be stopped or transferred to supply air, the trouble should be cleared immediately, and the
protection times are not counted.
2. Frequency limited
If T
Limited frequency temperature during discharging
≤T
Discharge
T
frequency reducing temperature at normal speed during discharging
, you should
limit the frequency raising of compressor.
3. Reducing frequency at normal speed and stopping machine:
If T
frequency reducing temperature at normal speed during discharging
≤T
Discharge
T
frequency reducing temperature at high speed during discharging
you should adjust the compressor frequency by reducing 8Hz/90s till the lower limit; After it was running 90s at
the lower limit, if T
frequency reducing temperature at normal speed during discharging
≤T
Discharge
, you should discharge to protect
machine stopping;
4. Reducing frequency at high speed and power turn-off:
If T
frequency reducing temperature at high speed during discharging
≤T
Discharge
T
Stop temperature during discharging
you should adjust
the compressor frequency by reducing 30Hz/90s till the lower limit; After it was running 90s at the lower limit, if
T
frequency reducing temperature at normal speed during discharging
≤T
Discharge
, you should discharge to protect machine stopping;