Thermistor Functions - Daikin FTX20K(2)V1B Service Manual

Thermistor Functions

2. Thermistor Functions

1. The outdoor heat exchanger thermistor is used for controlling the target discharge pipe
(1) Outdoor Heat
Exchanger
Thermistor
2. In cooling operation, the outdoor heat exchanger thermistor is used for detecting the
3. In cooling operation, the outdoor heat exchanger thermistor is used for high pressure
1. The discharge pipe thermistor is used for controlling discharge pipe temperature. If the
(2) Discharge
Pipe Thermistor
2. The discharge pipe thermistor is used for detecting disconnection of the discharge pipe
1. The indoor heat exchanger thermistor is used for controlling the target discharge pipe
(3) Indoor Heat
Exchanger
Thermistor
2. In cooling operation, the indoor heat exchanger thermistor is used for freeze-up protection
3. In heating operation, the indoor heat exchanger thermistor is used for detecting the
25
(1)
Four way valve
(2)
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.
disconnection of the discharge pipe thermistor. When the discharge pipe temperature drops
below the outdoor heat exchanger temperature by more than a certain value, the discharge
pipe thermistor is judged as disconnected.
protection.
discharge pipe temperature (used in place of the inner temperature of the compressor) rises
abnormally, the operating frequency becomes lower or the operation halts.
thermistor.
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.
disconnection of the discharge pipe thermistor. When the discharge pipe temperature drops
below the indoor heat exchanger temperature by more than a certain value, the discharge
pipe thermistor is judged as disconnected.
Electronic
expansion valve
(3)
Compressor
SiBE041525F
(R14247)
Functions and Control