Off Defrost Operation Control - Fujitsu ARYG72LHTA Service Instruction

1-19. OFF DEFROST OPEARTION 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 -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 shown in Table 15.
( Table 15 : OFF Defrost Release Condition )
Release Condition
After compressor operation time passed for 1 minute, when
a high-pressure sensor detected more than 2.09MPag.
Compressor operation time has passed 15 minute
OFF Defrost Flow Chart
Outdoor heat exchanger temp. :
Below -4°C
Compressor integrating operation :
Over 30 minutes
After compressor operation time passed for 1 minute, when
a high-pressure sensor detected more than 2.09MPag.
Compressor ON time : Maximum 15 minutes
or
Heating operation stop
and
Defrost start
Defrost Indicator:
[Operation lamp]
6 sec ON / 2 sec OFF
or
Defrost end
01-17
s.
.