3.3 E3/E4: T1C1/T2C2 Temperature sensor error
Digital display output
Description
E3 indicates malfunction of subcooler outlet temperature sensor (T1C1).
E4 indicates malfunction of subcooler outlet temperature sensor (T2C2).
All units stop running.
Error code is displayed on the malfunction MS box.
The indoor unit display board or wired controller connected to this MS displays "F8”.
Trigger / recover condition
Trigger condition: The main control board cannot receive the feedback signal of temperature sensor T1C1 or T2C2.
Recover condition: The main control board can receive the feedback signal of temperature sensor T1C1 or T2C2.
Reset method: Resume automatically.
Possible causes
Temperature sensor not connected properly or has malfunction.
MS main PCB is damaged.
Procedure
Notes:
1. Measure sensor resistance. If the resistance is too low, the sensor has short-circuited. If the resistance is not consistent with the sensor’s resistance
characteristics table, the sensor has failed. Refer to Table 6-4.1 in Part 6, 4.1 “Temperature Sensor Resistance Characteristics”.