Sinclair SCV-1400EB, Service Manual

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5.34 PA troubleshooting
Digital display output
Description

PA indicates abnormal water inlet and outlet temperature difference protection.

All units stop running.
 Error code is only displayed on main PCB and user interface.
Possible causes

Water temperature sensor damaged

Inlet and outlet water temperature sensor are in the inversely position
 Water flow is too low

Main control board damaged
Procedure
PA
Check whether inlet and outlet water
temperature sensor are in the inversely
position
Yes
Change the position of inlet and outlet
water temperature sensor
No
Water flow is too low
Yes
Check the water system cleanliness
No
Water Temperature sensor 1 damaged
Yes
Replace water temperature sensor
No
Replace main control board
Note:
1. For SCV-750EB and SCV-1400EB, inlet and outlet water temperature sensor connection port is CN4 on the main PCB (labeled 29 in Part 4, 2.2.1 Main PCB
component). 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”.
2. For SCV-900EB and SCV-1800EB, inlet and outlet water temperature sensor connection port is CN31 on the main PCB (labeled 31 in Part 4, 2.2.1 Main PCB
component). 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”.