Fujitsu AG * V12LAC Series, Service Instruction

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20. OFF DEFROST OPEARTION CONTROL
(1). OFF DEFROST OPERATION CONDITION
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.
In heating operation, the outdoor heat exchanger temperature is less than -4°C, and
compressor operation integrating time lasts for more than 30 minutes.
AG*V09/ 12LAC
AG*V14LAC
OFF Defrost Flow Chart
Heating operation stop
Outdoor heat exchanger temperature:
Below -4°C
and
Compressor integrating operation:
Over 30 minutes
Defrost start
Defrost Indicater:
[Operation lamp]
Outdoor heat exchanger temperature:
Over 10°C / 16°C
or
Compressor ON time:
Over 15 minutes
Defrost end
(2). OFF DEFROST END CONDITION
Release Condition
Outdoor heat exchanger temperature sensor value is higher than 16°C or
Compressor operation time has passed 15 minutes.
Outdoor heat exchanger temperature sensor value is higher than 10°C or
Compressor operation time has passed 15 minutes.
7 sec ON / 2 sec OFF
05-16