Low Hz High Pressure Limit; Defrost Control - Daikin Sky Air B-Series R-410A Service Manual

Si21-205

3.11 Low Hz High Pressure Limit

Outline Heat Pump Only
Set the upper limit of high pressure in a low Hz zone. Set the upper limit of the indoor heat
exchanger temperature by its operating frequency of Hz. Separate into three zones, reset zone,
unchanged zone and drooping zone and the frequency control must be carried out in such
zones.
Detail
Separate into Zones
Note: Drooping: The system stops 2 minutes after staying in the drooping zone.

3.12 Defrost Control

Outline Heat Pump Only
Defrosting is carried out by the cooling cycle (reverse cycle). The defrosting time or outdoor
heat exchanger temperature must be more than its fixed value when finishing.
Detail
Conditions for Starting Defrost
The starting conditions must be made with the outdoor air temperature and heat exchanger
temperature. Under the conditions that the system is in heating operation, 6 minutes after the
compressor is started and more than 44 minutes of accumulated time pass since the start of the
operation or ending the defrosting.
Conditions for Canceling Defrost
The judgment must be made with heat exchanger temperature. (4˚C~12˚C)
Function and Control
Highest heat
exchanger
temperature
among the
operating rooms
Frequency
60sec.
ON
Compressor
OFF
ON
Four way valve
OFF
ON
Fan
OFF
Electronic expansion
450pps
valve opening
Drooping zone
Reset zone
0Hz
120sec.
460 sec.
5sec.
450pps
Outdoor Unit (50/60 class)
Unchanged
zone
45sec.
5sec.
450pps
Initial opening
(R2832)
PI control
111