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SiUS30-1301
Outline of Control (Indoor Unit)
Function and Control
75
9.9
Heater Control (Optional PCB KRP1B ... is required.)
The heater control is conducted in the following manner.
[Normal control]
While in heating, the heater control (ON/
OFF) is conducted as shown on the right.
[Overload control]
When the system is overloaded in
heating, the heater will be turned
OFF in the following 2 manners.
(1) The heater control (ON/OFF) is
conducted through the liquid pipe
temperature (R2T) of the indoor
unit.
(2) The heater control (ON/OFF) is
conducted by converting the
heater temperature into the
condensing pressure equivalent
saturated temperature (Tc)
according to the temperature
detection through the high
pressure sensor (S1NPH) of the condensing unit.
[Fan residual operation]
While the heater turns OFF, in order to prevent the activation of the thermal protector, the fan
conducts residual operation for a given period of time after the heater turns OFF. (This operation is
conducted regardless of with or without heater equipped.)
Residual operation time = 100 seconds on ceiling suspended type or 60 seconds on other types
ON
Set temperature
OFF
3.6ºF
3.6ºF
ON
109.4ºF
122ºF Liquid pipe temperature
OFF
ON
122ºF
140ºF
OFF
Condensing pressure
equivalent saturated
temperature