Fujitsu R410A Service Instruction

23. DEFROST OPERATION CONTROL
1. CONDITION OF STARTING THE DEFROST OPERATION
Integrating defrost
( OFF count defrost )
2. CONDITION OF THE DEFROST OPERATION COMPLETION
Defrost operation is released when the conditions becomes as shown in Table 22.
( Table 22 : Condition of defrost release )
Release Condition
Outdoor heat exchanger temperature is higher than 55.4°F(13°C)
or
Compressor operation time has passed 15 minutes.
The defrost operation starts as shown in the following Table 18, 19, 20 and 21.
From 2nd and later
defrost after
starting operation
Less than 35 minutes More than 35 minutes
Does not operate
Compressor integrating operation time
( Table 18 : Condition of 1st defrost operation )
1st defrost
after
starting operation
Compressor integrating operation time
Less than 17 minutes More than 17 minutes More than 57 minutes
Does not operate
Compressor integrating operation time
( Table 21 : Condition of Integrating ( OFF count ) defrost operation )
( Table 19 : Condition of 2nd defrost operation )
23. DEFROST OPERATION CONTROL
Compressor integrating operation time
Tn < -77°F (-25°C)
Tn - Tn10 < -41°F (5°C) ( Tn < -42.8°F (6°C))
Tn - Tnb < -35.6°F (2°C) ( Tn < -42.8°F (6°C))
=
=
=
Tn10 : Temperature of continuous operation at 10 minutes.
Tnb : Back 5 minutes temperature.
Tn : Outdoor heat exchanger temperature.
Ta : Outdoor temperature.
More than 210 minutes
( For long continuous operation )
Integrating defrost
More than 210 minutes
( For long continuous operation )
(and after 30 minutes, if the 26.6°F (-3°C)) (and after 5 minutes, if the 23°F (-5°C))
(and after 5 minutes, if the 23°F (-5°C))
( Table 20 : Condition of Integrating defrost operation )
Compressor integrating operation time
Less than 10 minutes
( For intermittent operation )
OFF count of the compressor : 40 times
01-15
䐟
䐠
䐡
If the compressor continuous operation time is less than 10 minutes,
the OFF number of the compressor is counted.
If any defrost operated, the compressor OFF count is cleared.
(and after 5 minutes, in the 41°F(5°C))
Ta - Tn > 41°F(5°C)
and
=
Tn < 15.8°F(-9°C)
=
Tn < 26.6°F(-3°C)
=
Tn < 23°F(-5°C)
=
Tn < 23°F(-5°C)
=

Fujitsu R410A Specifications

General

Brand	Fujitsu
Model	R410A
Category	Air Conditioner
Language	English