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Controller Operation
Controller Operation
8
㸧
IR reception
System receives commands from handset.
9
㸧
Cool mode
In Cool mode, compressor will cut in if Tr - Ts >= 0.5°C and cut out if Tr - Ts =< (-1.0)°C,
subject to 3 minutes protections and minimum run time. Indoor fan speed can be manually
selected or determine by the system in Auto Fan speed according to the return air temp.
10
㸧
Dry mode
Indoor fan runs at low speed.
Compressor will cut out if:-
a) It has run for 10 minutes continuously or
b) Tr - Ts =< (-1.0)°C
It is then allow to cut in if:-
a) It has stop for 5 minutes and
b) Tr - Ts >= 0.5°C
11
㸧
Fan mode
Only High, Medium and Low speed selection is allowed (KFDH075,100 only) .
12
㸧
Error code
If multiple faults happen at the same time, the corresponding error code will be shown one after another.
13
㸧
Off mode
All output are off during system off state except indoor fan which are subject to the
minimum operating time guard where applicable.
6
㸧
Compressor protection
a) Comp restart protection
1. 3 minutes protection
2. Hardware Anti short cycle timer
Should the power supply is cut off and resume, compressor 3 minutes
protection control logic is as below:-
7
㸧
Temperature sensor fault
a) Return air sensor
Monitor continuously
b) Indoor coil sensor
• If comp is turned on, monitoring is done 5 minutes after comp running.
• If comp is stop, monitor continuously
Upon happening of any sensor fault, system is forced to Fan mode. It will then resume
to normal mode upon clearance of fault.
b) 90S minimum run time (compressor)
c) Indoor coil anti freeze
Power outage duration Restart protection timer
<180S 180S—
243S
>180S
< 63S
Fault Error
code
Room sensor fault
E1
Indoor coil sensor fault E2
Comp fault
E4