Solar Operation (Optional) - Panasonic WH-MXF09D3E8 Service Manual

2. Backup heater anti freeze control:
Backup heater turns ON when ALL the below conditions are fulfilled:
Water inlet/outlet temp. < 6°C
o
Water pump circulation anti freeze control activated, and water pump ON for 4 minutes
o
Backup heater turns OFF when ANY of the below conditions is fulfilled:
Water inlet/outlet temp. > 28°C
o
Water pump circulation anti freeze control deactivated/water pump OFF
o
However, if backup heater is abnormal (H70), then backup heater anti freeze control will not activate.

12.16 Solar Operation (Optional)

12.16.1 Solar Operation
1 External solar heat source signal can be connect to unit for proper control of heat source switching during
tank boiling time.
2 Control according to preset whether solar priority is set or not.
3 When tank connection is NOT set at SETTING mode, solar operation is disabled.
4 When Pump A (from solar pump station) is detected On through connection Y3 and Y4, then the Solar pump
3 Way Valve is requested ON (Refer to figure below).
12.16.2 Solar Operation Control
When solar priority is SET
1 Operation condition:
a 3 way valve operates if all of the following conditions are fulfilled:
Power On. (regardless operation ON or OFF)
There is operation request from solar pump station.
Tank hot water temp is below solar on upper limit temp 72°C.
2 Stop condition:
a 3 way valve stops operating when:
No power supply to unit OR
There is NO operation request from solar pump station OR
Tank hot water temp is above solar off upper limit temp 80°C.
* heat pump OFF OR operate to room side when solar pump operate during solar priority set.
* booster heater OFF when solar pump operate during solar priority set.
When solar priority is NOT SET
1 Operation condition:
a 3 way valve operates if all of the following conditions are fulfilled:
Power On. (regardless operation ON or OFF).
There is operation request from solar pump station.
Tank hot water temp is below solar on upper limit temp 72°C.
Heat pump thermo OFF in tank mode OR Heat pump operate to room side
(during operation ON and tank mode selected).
61