Gree FGR20/BNa-M

14
Duct Type Split Air Conditioner
Service Manual
CONTROL
2.3 Heating Mode
Compressor
Outdoor fan
Indoor fan
4-way valve
OFF
ON
OFF
ON
OFF
OFF
ON
Run under set
speed
Time
OFF
OFF
ON
ON
Anti-cold air
Auxiliary heater
OFF
OFF
OFF
OFF
ON
Running condition
is met
Blowing residual heat
Manually OFF
Heating mode
1s 20s 10s 15s 45s 60s
When Tambient
≤
Tset-1
℃
, the unit will run in heating mode. In this case, compressor and outdoor fan run;
Indoor fan runs at setting speed and under the condition of anti-cold air.
When Tambient
≥
Tset+1
℃
,compressor and outdoor fan stop running, the 4-way valve is still energized
and indoor fan runs under the condition of blowing residual heat.
When Tset -1
℃＜
Tambient
＜
Tset+1
℃
,the unit will keep its previous running state.
2.4 Defrosting
1s10s 10s
ON
ON
Run at set speed
OFF
End defrosting
ON
OFF
OFF
OFF
ON
ON ON
ON
ON
ON
Compressor
Outdoor fan
Auxiliary heater
Indoor fan
4-way valve
Satrt defrostig
Running conditions
are met
Time
Anti cold air
Defroting mode
Defrosting start condition: If the unit heats for 44min accumulatively, the compressor continuously runs for
4min and 50s, and T condensate
≤
-5
℃
,defrosting will start. If there is auxiliary heater, it will stop rstly and then
the 4-way valve, indoor fan and outdoor fan will stop in 10s and the compressor will compulsively run.
Defrosting end condition: If the unit defrosts for 10min or T condensate
≥
10
℃
, defrosting will end, 4-way
valve will start running, outdoor fan will run, and compressor compulsively run. Indoor fan will run under the anti-
cold air condition.