Midea VRF Series Service Manual page 100

Procedure
F3/F5/F9/FA/Fb/FC/Fd
Temperature sensor connection on
outdoor main PCB is loose
Temperature sensor has short-circuited
Replace the outdoor main PCB
Notes:
1. Injection liquid temperature sensor (T6A) and subcooling gas temperature sensor (T6B) connection are port CN8 and CN6 on the outdoor main PCB. Liquid
pipe temperature sensor (T5) and Heat sink Temperature sensor (T9) error connection are port CN12 and CN14 on the outdoor main PCB. Heat exchanger
gas Temperature sensor (T8) and Heat exchanger liquid Temperature sensor (TL) connection are port CN7 on the outdoor main PCB. Suction Temperature
sensor (T7) connection is port CN10 on the outdoor main PCB.
2. 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 ".
1
No
2
or failed
No
Yes
Ensure the sensor is connected properly
Yes
Replace the sensor
V6R VRF 50/60Hz
99