Sinclair SCV-750EB Service Manual page 105

Procedure
For SCV-750EB and SCV-1400EB
Air side heat exchanger tube temperature
sensor "T3a / T3b" is loose
Fan motor wiring connection is wrong
Air side heat exchanger tube temperature
sensor "T3a / T3b" has short-circuited or
The air side heat exchanger heat exchange
The fan or fan motor is blocked or damaged
Replace outdoor main PCB
Notes:
1. Air side heat exchanger tube temperature sensor "T3a / T3b" connection port is CN37/CN16 on the main PCB (labeled 22,24 in Part 4, 2.2.1 Main PCB
component)
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 Part 4, 6.1 "Temperature Sensor Resistance Characteristics".
3. Check air side heat exchanger, fan(s) and air outlets for dirt/blockages.
P7
1
No
No
failed 2
No
is poor 3
No
No
Ensure the temperature sensor is
Yes
connected properly
Ensure fan motor wiring is connected
Yes
Yes
Replace the temperature sensor
Yes
Inspect the system and fix the error
Yes
Inspect the system and fix the error
properly
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