62
11
Outline of control
Outdoor units
Item Operation explanation and applied data, etc. Remarks
12. Defrost 3) For the slave outdoor units
control • The compressors 1 and 2 are kept on. Should they be off they will be
(reverse switched on.
defrost • After the signal to finish the defrost operation is received from the master
method) outdoor units, the 4-way valves become switched on.
• The capacity of the compressors is controlled according to the on/off signals
from the master outdoor units thereon.
(5) SV41, 42 low pressure release control
This prevents the low pressure level relaxing during the defrost control operation. The
master outdoor units and slave outdoor units have their own control over this action
when the defrost/heating operation is in progress.
1) Control details
When PS pressure 0.5 kgf/cm
2
G, the control switches SV41 and SV42 on.
When PS pressure 1.0 kgf/cm
2
G, SV41, and 42 are switched off.
13. Cold draught (1) During the heating operation, the indoor fan is controlled according to the • “Preheat defrost”
prevention temperature that is detected by TC2 (indoor heat exchange sensor). light displayed
control
(°C)
30
26
20
16
A
C
B
C zone: OFF
A zone: set fan operation from the
remote controller
B zone: low fan speed
14. IDU (1) To prevent the IDU heat exchanger remaining hot after operation has stopped the
exchanger indoor fan operates in low fan speed for approximately 30 seconds.
heat removal
To Next Page
Loading...
