Defrost Operation Control - Fujitsu ASU9RLQ Service Instructions Manual

19. DEFROST OPERATION CONTROL

(1). CONDITION OF STARTING THE DEFROST OPERATION
The defrost operation starts when the outdoor heat exchanger temperature sensor detects
the temperature lower than the values shown in Table 13.
(Table 13 : Condition of starting Defrost Operation)
1 time defrosting
ST
after starting
operation
Defrosting after 2
nd
time upon starting
operation
(2). CONDITION OF THE DEFROST OPERATION COMPLETION
Defrost operation is released when the conditions become as shown in Table 14.
(Table 14 : Defrost Release Condition)
ASU9RLQ
ASU12RLQ
ASU18RL
Less than 20 minutes 20 to 60 minutes 60 minutes to 4 hours
ASU9RLQ
ASU12RLQ
Does not operate
ASU18CL
ASU18RL
Less than 35 minutes
ASU9RLQ
ASU12RLQ
Does not operate
ASU18CL
ASU18RL
Outdoor heat exchanger temperature sensor value is higher than 61°F(16°C) or
Compressor operation time has passed 15 minutes.
Outdoor heat exchanger temperature sensor value is higher than 61°F(16°C) or
Compressor operation time has passed 15 minutes.
Outdoor heat exchanger temperature sensor value is higher than 50°F(10°C) or
Compressor operation time has passed 15 minutes.
Compressor operating time
- 16°F(-9°C)
- 16°F(-9°C)
-
- 16°F(-9°C)
Compressor operating time
35 minutes to
4 hours
- 21°F(-6°C)
- 21°F(-6°C)
-
- 21°F(-6°C)
Release Condition
05-14
After 4 hours
- 23°F(-5°C) - 27°F(-3°C)
- 23°F(-5°C) - 27°F(-3°C)
-
-
- 23°F(-5°C)
- 27°F(-3°C)
After 4 hours
- 27°F(-3°C)
- 27°F(-3°C)
-
- 27°F(-3°C)