Off Defrost Operation Control - Fujitsu AMUG24LMAS Service Manual

12. OFF DEFROST OPERATION CONTROL

When operation stops in the [Heating operation] mode, if frost is adhered to the outdoor unit heat
exchanger, the defrost operation will proceed automatically. In this time, if indoor unit operation
lamp flashes slowly (7 sec ON / 2 sec OFF), the outdoor unit will allow the heat exchanger to defrost,
and then stop.
1. OFF DEFROST OPERATION CONDITION
In heating operation, the outdoor heat-exchanger temperature is less than 24.8°F (-4°C), and
compressor operation integrating time lasts for more than 30 minutes.
2. OFF DEFROST RELEASE CONDITION
OFF defrost operation is released when the conditions becomes as below.
Outdoor heat-exchanger temperature is higher than
Compressor operation time has passed 15 minutes.
3. OFF DEFROST FLOWCHART
Outdoor heat-exchanger temperature : Over
or
Heating operation stop
Outdoor heat exchanger temp. :
Below 24.8°F (-4°C)
and
Compressor integrating operation :
Over 30 minutes
Defrost start
Defrost Indicator: [Operation lamp]
6 sec ON / 2 sec OFF (AOU24,30RGLX)
7 sec ON / 2 sec OFF (AOUG36,48LMAS1)
Compressor ON time : Maximum 15 minutes
Defrost end
55.4°F (13°C) (AOU24, 30RGLX)
59.0°F (15°C) (AOUG36, 48LMAS1)
55.4°F (13°C)
59.0°F (15°C)
or
04-28
(AOU24, 30RGLX)
(AOUG36, 48LMAS1)