E3/E4: T1C1/T2C2 Temperature Sensor Error - Midea VRF Series Service Manual

V6R VRF 50/60Hz

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
Temperature sensor connection on MS
main PCB is loose
Temperature sensor has short-circuited
Replace the MS main PCB
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".
152
E3/E4
No
1
or failed
No
Yes
Ensure the sensor is connected properly
Yes
Replace the sensor