Defrost Operation In Heating Operation Stopped - Fujitsu ASTG30KMTC Service Manual

6-1. Defrost operation in heating operation stopped

If the outdoor unit is frosted when stopping the heating operation, it stops after performing the auto-
matic defrosting operation.
In this time, if the indoor unit operation lamp flashes slowly (6 sec on/2 sec off), the outdoor unit al-
low the heat exchanger to defrost, and then stop.
Triggering condition
•
When all of the following conditions are satisfied in heating operation
– Compressor operation integrating time: 30 minutes or more
– Compressor continuous operation time: 10 minutes or more
– Outdoor unit heat exchanger temperature: -4°C or less
Release condition
•
The defrost operation is released when the condition become as shown below.
Outdoor unit heat exchanger temperature
(after 1 minute or later since compressor start)
Compressor operation time
Flowchart
•
6-1. Defrost operation in heating operation stopped
30 model
34 model
Heating operation stop
Outdoor heat exchanger temperature:
Below -4°C
Compressor continuous operation:
Over 10 minutes
Compressor integrating operation:
Over 30 minutes
Defrost start
Defrost Indicater:
Operation lamp
7 sec on/ 2 sec off
Outdoor heat exchanger temperature:
Over +13°C (30), +12°C (34)
or
Compressor on time: Max. 15 minutes
Defrost end
- (04-19) -
+13°C or more
+12°C or more
15 minutes
6. Defrost operation control