55
3-7 Service functions
(1) Compulsory defrosting
1
When all of the following conditions are satisfied, pressing SW2 starts the compulsory defrosting.
●
During HEAT mode
●
The compressor is ON.
●
The outdoor coil temperature is being displayed by LED. (Outdoor controller board dip switch SW3-1 : OFF, SW3-2 :
ON)
●
The outdoor coil thermistor reads 8°C or below.
2
The operation state and the termination conditions of the compulsory defrosting are the same as those of the normal
defrosting. As an exception, the defrost interval after the defrosting completion is 50 minutes.
(2) Fixed fan-output
While the compressor is operating (except during defrosting) and the fan output step is indicated by LED, pressing SW2
fixes the fan output. The fixed fan-output can be released when any of the following conditions are satisfied.
1
SW2 is pressed again.
2
SW3 setting is changed.
3
The compressor stops.
4
Defrosting operation starts.
(3) Function of switches on the outdoor controller board
SW1: Clears the check code memory (push-button switch)
SW2: Switches the output state indication and the check code display (push-button switch)
SW3-1,2: Switches the output state indication items (dip switch)
For further information, refer to page 59.
(4) 100% fan output
Fan output is fixed to 100% by shorting the connector CN22. However, the fan stops during compressor OFF or defrosting.
Open-circuit of CN22 restarts the normal fan control.
(5) Time shortening
Short circuit of the connector CN21 shortens the time as follows
1
Fan control period: 30 seconds
→
3 seconds
2
Three-minutes time delay function : 3 minutes
→
3 seconds
3
Max. time of defrosting : 15 minutes
→
15 seconds
4
Defrost interval : 30 ~ 120 minutes
→
3 ~ 12 seconds
5
Compressor ON/OFF time for bypass valve ON/OFF : 30 minutes
→
3 seconds
6
Compressor ON time to start other functions : x minutes
→
x seconds
7
Crankcase heater operation : 1 hour
→
6 seconds