Protection Control For Heating Operation - Panasonic WH-MDC06E3E5 Service Manual

13.1.10 Crank Case Heater Control
Purpose:
- For compressor protection during low outdoor ambient operation (during heating low temperature operation).
Control content:
a. Trigger heater START condition
When the outdoor air temperature is 4°C or below, and discharge temperature is 12°C or below.
o
b. Resetting heater STOP condition
when the outdoor air temperature exceeds entry condition 6°C.
1.
when the discharge temperature exceeds entry condition 19°C.
2.
13.2

Protection Control for Heating Operation

13.2.1 Outdoor Air Temperature Control
The maximum current value is regulated when the outdoor air temperature rises above 14°C in order to avoid
compressor overloading.
13.2.2 Deice Operation
When outdoor pipe temperature and outdoor air temperature is low, deice operation start where outdoor fan motor
stop.
13.2.3 Heat-exchanger (hot water coil) protection control
Backup heater ON condition:-
water inlet temperature < 18°C AND
o
outdoor ambient temperature < 10°C
o
Backup heater OFF condition:-
water inlet temperature > 20°C OR
o
outdoor ambient temperature > 13°C
o
However this control will take place 29 minutes after compressor restart.
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