Explanation Of Operation - Panasonic CU-E18CKR Service Manual

stage.
2. The deice will be performed only after 1 hour from when the
operation has started.
3. When Comp. OFF by the sequence No. 1, 6, 7 compressor can
restart back without 3 minutes waits (immediate restart).
Outdoor heat exchanger temperature
a
15°C
b
18°C
c
25°C

3. Explanation of operation

1) Before the deice is started, compressor frequency is set to the specified value for T0-timer.
2) After deice is started, the 4-way valve, OD Fan and ID fan are OFF.
3) After 4-way valve is OFF for 30 s, compressor frequency is set to the specified value.
4) Before deice is ended, if the outdoor heat exchanger temperature exceeds a°C, set compressor
frequency and expansion valve to the specified values.
5) When outdoor heat exchanger temperature exceeds b°C, or 10.5 minutes has passed since
valve is OFF, operation at timer T5 will be started.
6) After the above 5) operation, if the specified time has passed, the deice operation ending signal
be produced. The comp. Hz is set to the specified value and at the same time outdoor fan motor
signalis produced.
7) After T6 the deice ending signal is produced, 4-way valve is set to ON, indoor fan is ON, Compressor
frequency is FREE, and return to normal heating operation.
4. Deice operation judgement condition
When any of below a, b, c, d condition is satisfied, deice signal is
produced.
A. Continuously, outdoor heat exchanger temperature < 3°C for
120 minutes and outdoor heat exchanger temperature < -5°C for
3 minutes and outdoor air temperature > -1°C and Comp. is ON.