2-22. E: 73. Outdoor unit heat exchanger thermistor error
(Outdoor unit)
Indicator
→ired remote
controller
Error code E: 73
Detective actuator
Outdoor unit main PCB
→hen heat exchanger temperature thermistor open or
short circuit is detected at power on or while running the
compressor
Heat exchanger temperature
thermistor
Forecast of cause
Connector failure
Thermistor failure
Main PCB failure
Check point 1. Check connection of connector
• Check if connector is loose or removed.
• Check erroneous connection.
• Check if thermistor cable is open
Reset power when reinstalling due to removed connector or incorrect wiring.
Check point 2. Remove connector and check thermistor resistance value
• For the outdoor unit heat exchanger thermistor resistance value, refer to "Ther-
mistor resistance values" on page 03-53.
• If thermistor is either open or shorted, replace it and reset the power.
Check point 3. Check voltage of main PCB
Make sure circuit diagram of outdoor unit and check terminal voltage at thermistor
(DC 5.0 V).
NOTE: For details of thermistor connector, refer to "→iring diagrams" in Chapter 2.
TECHNICAL DATA AND PARTS LIST on page 02-22.
If the voltage does not appear, replace main PCB.
End
2-22. E: 73. Outdoor unit heat exchanger thermistor error (Outdoor unit) - (03-27) - 2. Troubleshooting with error code
TROUBLESHOOTING
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