Outdoor Unit Control - Airwell VVFA Series Service Manual

14. Outdoor Unit Control

1. Compressor startup control
After receiving the outdoor startup instruction, outdoor open SV1 30 seconds and then standby. When startup, the
compressor will keep for 3 min at 45rps (when Ta<40°C) or 3 min at 40rps (when Ta>=40°C). In cooling mode, meet
running 1min & (Td-CT)≥20°C or Ps≤0.1MPa (or max. running time is 3min),quite the startup control;
In heating mode, meet running 1min and & (Td-CT)≥20°C or Ps≤0.1MPa (or max. running time is 3min), quite the
startup control;
During startup, the high pressure protection, high exhaust protection and current protection is priority and the low
exhaust up frequency protection is shielded.
2. Compressor output control
Compressor Pd/Ps control, control the compressor frequency to output appropriate cooling/heating capacity.
The control at the end of the startup control.
2.1 In cooling mode:
According to the ambient temperature select target Ps automatically
Mode
Target Ps
Target Ps (set by dip
switch)
Target Ps
R value setting: Ta<-5°C, Target Ps: setting value -8°C
-5°C≤Ta<12°C, Target Ps is the slope value of setting value and (setting value -8°C)
2.2 In heating mode:
According to the piping length to select target Pd and also according to the ambient temperature select target Pd
automatically
Mode
Target Pd
Target Pd
Target Pd
(set by dip switch)
Target Pd
3. Outdoor fan motor control
3.1 In cooling mode:
Outdoor fan motor running control during cooling mode is in high COP and 100% RPM running as much as
possible.
Outdoor fan control in the operation of the refrigeration in the relation between high COP operation principle is to
100% as much as possible the RPM.
Pd is the main control standard.
Effect priority mode
(default)
Setting value -R°C
0
Setting value +2°C
Effect priority mode
(default)
Setting value +3°C
Setting value +2°C
48
Setting value -2°C
Energy-saving mode
Setting value -R°C
2
Setting value +2°C
Energy-saving mode
Setting value +3°C
Setting value +2°C
46
Setting value -2°C
38
Outdoor ambient Ps correction
temperature during running
Ta≤12°C
During running:
correct the Ps
12°C<Ta<40°C
according to the
compression ratio
Ta≥40°C
Outdoor ambient Pd correction during
temperature
Ta≥15°C
During running:
Ta≥7°C
correct the Pd
according to the
Ta≥-5°C
compression ratio
Ta<-5°C
running