Controls At Mode Changing / Start-Up - Daikin F-Series Service Manual

Control Specification
3.3

Controls at Mode Changing / Start-up

3.3.1 Preheating Operation
Outline Operate the inverter in the open phase operation with the conditions including the outdoor air
temperature, discharge pipe temperature, and fin temperature (internal temperature of PM1).
Detail Outside temperature
Outside temperature < 10°C
Control A
Control B
3.3.2 Four Way Valve Switching
Outline Heat Pump Only
During the heating operation current must be conducted and during cooling and defrosting
current must not be conducted. In order to eliminate the switching sound (as the four way valve
coil switches from ON to OFF) when the heating is stopped, the delay switch of the four way
valve must be carried out after the operation stopped.
Detail The OFF delay of four way valve
Energize the coil for 150 sec after unit operation is stopped.
3.3.3 Four Way Valve Operation Compensation
Outline Heat Pump Only
At the beginning of the operation as the four way valve is switched, acquire the differential
pressure required for activating the four way valve by having output the operating frequency,
which is more than a certain fixed frequency, for a certain fixed time.
Detail Starting Conditions
1. The MRC/W turns ON when the compressor starts for heating after the MRC/W has been
2. The MRC/W turns OFF when the compressor starts for cooling after the MRC/W has been
3. The compressor starts for the first time after reset.
4. The compressor starts after suspension caused by the trouble of cooling/heating
46
≥
10°C
ON condition
Discharge pipe temperature < 6°C
Fin temperature < 85°C
OFF condition
Discharge pipe temperature > 8°C
≥
Fin temperature 90°C
ON condition
Discharge pipe temperature < 10.5°C
Fin temperature < 85°C
OFF condition
Discharge pipe temperature > 12°C
≥
Fin temperature 90°C
OFF with compressor halted.
ON with compressor running.
changeover.
Set the lower limit frequency to 48 Hz for 70 seconds with any conditions 1 through 4 above.
→
Control A (preheating for normal state)
→
Control B (preheating of increased capacity)
SiBE04-705
Function and Control