Defrosting Operation - Daikin SkyAir RZQ200 · 250C7Y1B Service Manual

Outdoor Unit
2.4.5.9 Suction Pipe Superheat Protection Control (in Heating Operation Only)
In heating operation, controls compressor operating frequency to prevent oil from remaining in
the outdoor unit heat exchanger by the continuous operation of compressor at high superheated
degree of the suction pipe.
2.4.5.10 Anti-freeze Control (in Cooling Operation Only)
The thermostat is turned OFF when temperature and time meet the following conditions to
prevent the indoor heat exchanger from freezing:
OR
2.4.6 Oil Return, Defrosting Operation, etc.

2.4.6.1 Defrosting Operation

When heating operation, defrost operation is conducted to melt frost on outdoor unit heat
exchanger.
[Defrost starting condition]
&
"Frost upper limit time A" is determined as follows according to the "Field setting by remote
controller" (see P58).
Upper limit duration A of frost
The following table shows the upper limit duration A of frost according to defrost start setting
conditions (indoor remote controller field setting mode).
68
·
·
• Indoor heat exchanger temperature < -5°C for 1 minute continuously
• Indoor heat exchanger temperature < -1°C for an accumulated 40 minutes
Intelligent type
Defrosting starts when the following conditions have been realized.
·
Th2 ≤-3ºC
·
Th2≤0.4 ×Ta-5ºC
·
Defrost upper limit time A is met
·
·
Accumulated heating capacity is decreasing.
·
OR
&
·
Thermostat ON continues for 5 minutes or more.
Outdoor air temp. > -5°C
A value
Outdoor air temp. ≤ -5°C
Normal Control
Compressor step
Suction SH>8ºC
=Maximum frequency
Suction SH<8ºC for 1 minute continuously
Compressor step Compressor step
–1 step
Suction SH>8ºC for 30 seconds continuously
Suction pipe superheat control
Early defrost start
setting
40 minutes
40 minutes
+1 step
Late defrost start
Factory set
3 hours
6 hours
Function and Operation
SiBE26-701
setting
6 hours
8 hours