Freeze-Up Prevention - Daikin FTX25JVEA9 Service Manual

Si18-201
3.13

Freeze-Up Prevention

Outline According to the freeze prevention status sent from the BP unit, the compressor output
frequency is regulated to decrease the compressor capacity in order to prevent the indoor heat
exchanger from freezing.
Details Zones are produced based on the freeze prevention status signal sent from the BP unit (indoor
unit), and the freeze prevention control prevents freezing of the indoor unit.
A change of 2 Hz is made when each zone fluctuates.
The reset zone is set for 6 minutes when the operation mode is changed, for 30 seconds when
the number of operating room units increase, and for 30 seconds when the number of operating
room units decrease.
With each operation of the freeze prevention operation counter, the drooping speed is increased
by 1 Hz.
Main Functions
Reset zone
No-change zone
Drooping zone
Drooping speed : 2Hz/20sec
(M1019)
System control
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