Daikin FTKS20D3VMW Service Manual page 92

SiENBE12-713
D Indoor Heat 1. The indoor heat exchanger thermistors are used for controlling target discharge
Exchanger
Thermistor
2. The indoor heat exchanger thermistors are used for preventing freezing.
3. The indoor heat exchanger thermistors are used for anti-icing control.
4. The indoor heat exchanger thermistors are used for detecting incorrect wiring.
Function and Control
temperature.
The system sets a target discharge pipe temperature according to the outdoor and indoor
heat exchanger temperature, and controls the electronic expansion valve opening so that
the target discharge temperature can be obtained.
During the cooling operation, if the temperature drops abnormally, the operating frequency
becomes lower, then the operation halts.
During the cooling operation, if the heat exchanger temperature in the room where operation
is halted becomes -1°C, or if the room temperature - heat exchanger temperature in the
room where operation is halted becomes ≥10°C, it is assumed as icing.
During checking incorrect wiring, refrigerant is passed in order from the port A to detect a
heat exchanger temperature, and then wiring and piping will be checked.
Function of Main Structural Parts
81