Daikin MKS-T Series Service Manual page 81

SiSG121917E
(5) Liquid Pipe
 Liquid pipe thermistor is used to protect the compressor against liquid attack during cooling
Thermistor
 In case of low outdoor temperature operation, the system compares the indoor heat
(6) Indoor Heat
 The indoor heat exchanger thermistor is used for controlling the target discharge pipe
Exchanger
Thermistor
 In cooling operation, the indoor heat exchanger thermistor is used for freeze-up protection
 In cooling operation, the indoor heat exchanger thermistor is used for anti-icing function. If
 The indoor heat exchanger thermistor is used for detecting incorrect wiring. During wiring
(7) Room  The room temperature thermistor detects the room air temperature and is used for
Temperature
Thermistor
Part 4 Functions and Control
operation.
exchanger temperature with the liquid pipe temperature to detect disturbances in the
refrigerant flow. If any, the system adjusts the opening of the electronic expansion valve to
control the refrigerant flow.
temperature. The system sets the 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 pipe temperature can be obtained.
control. If the indoor heat exchanger temperature drops abnormally, the operating frequency
becomes lower or the operation halts.
any of the following conditions are met in the room where operation halts, it is assumed as
icing.
The conditions are
Tc  – 1°C
Ta – Tc  10°C
where Ta is the room temperature and Tc is the indoor heat exchanger temperature.
check operation, the indoor heat exchanger thermistor detects the heat exchanger
temperature. The heat exchanger temperature is used to check the wiring and the piping.
controlling the room air temperature.
Thermistor Functions
76