Daikin FTXA20A Service Manual page 145

To perform an electrical check of the specific thermistor
FTXA20~50A(W)(S)(T) + FTXA20~50B(B)(S)(T) + RXA42+50A +
RXA20~35A(9) + RXA42+50B
Split Stylish R32
ESIE18-03D – 2021.05
Is the thermistor correctly installed
(thermal contact between the
thermistor and the piping)?
Yes
No
1 First perform a mechanical check of the thermistor, see
4
procedures" [ 144].
2 Locate the thermistor.
INFORMATION
Remove the thermistor from its holder if not reachable with a contact thermometer.
3 Measure the temperature using a contact thermometer.
Name Symbol
Air R1T
thermistor
Heat R2T
exchanger
thermistor
Discharge R3T
pipe
thermistor
Heat R1T
exchanger
thermistor
Indoor unit R2T
air (room)
thermistor
4 Determine the thermistor resistance that matches the measured
temperature.
Thermistor – Table A
T °C kΩ T °C
–20 197.81 10
Action
Perform an electrical check of the
specific thermistor, see
procedures" [
Correctly install the thermistor, see
"Repair procedures" [
Location Connector
(PCB) (pins)
Main (O/U) S90:1‑2
Main (O/U) S90:3‑4
Main (O/U) S90:5‑6
Main (I/U) S501:1‑2
Humidity S600:1‑2
sensor PCB
A5P on
main PCB (I/
U)
kΩ T °C kΩ
39.96 40 10.63
2 Components
|
"Checking
4
144].
4
148].
"Checking
Inter- Referen
mediate ce
connector (table)
(pins)
- A
- A
- A
- A
CN1:1‑2 (on A
A5P)
T °C kΩ
70 3.44
Service manual
145