4
Room Temperature reading (T
room
)
2 ZONE
There are 2 room temperature sensors. One is installed at the return air point of Fan Coil Unit. Another is at the Display unit.
Jumper at OP2 is for selection of the following algorithm.
a) Jumper OP2 is
not
inserted. The room temperature will be read from only the sensor at return air point for all modes of
operation.
b) Jumper OP2 is inserted: In COOL or DRY operation, the room temperature will be read from the sensor at the return
air point of FCU. In HEAT operation, the room temperature will be read from the sensor at the Display unit. When any
one of the sensors have failed (short/open circuit), the temperature will be read from another sensor.
Fan
The system will operate as Fan only. The SLEEP, TEMP
and TEMP
buttons are not used.
Cool
The system will operate as the cooling unit. The compressor will
Operate if
T
room
> T
set
+1
Stop if
T
room
<
T
set
However, the compressor is subjected to a 3-minute delay protection each time it stops.
Dry
The system will operate as the Dehumidifier.
Define
T
s
=
setting temperature
T
r
=
room temperature
Zone A is the area where
T
r
– T
s
> 2
o
C
Zone B is the area where
0
o
C <T
r
– T
s
< 1
o
C
Zone C is the area where
-2
o
C < T
r
– T
s
< -1
o
C
Zone D is the area where
T
r
– T
s
< -4
o
C
Other temperature rang is called
dead band.
Which the system is considered to be in the previous zone.