A.O. Smith T-M50 ASME Service Manual page 44

Error Code
Pump failure
631
1 Check whether the pump connected to central computer board works
properly.
Error Code
Water control valve fault
(Flow adjustment function)
651
1 Left and/or Right PCB and flow adjustment valve fault
(Refer to section 10-9 & 10-14)
V isual inspection of Water control valve: connection/breakage of wires,
motor drive locked due to scale buildup, and/or water leakage.
Normal: 13.0 to 16 VDC between (blue-brown)
Normal: ON:12.5 to 16.0 V / OFF: 0 to 1 V
Normal: 1 V Less than (0˚ position)
V isual inspection PCB: connection/breakage of wires and/or burn marks on
the computer board.
Error Code
Water control valve fault
(Bypass valve function)
661
1 Left and/or Right PCB and bypass valve fault
(Refer to section 10-9 & 10-14)
V isual inspection of Water control valve: connection/breakage of wires,
motor drive locked due to scale buildup, and/or water leakage.
Normal: 13.0 to 16 VDC between (blue-brown)
Normal: ON:12.5 to 16.0 VDC / OFF: 0 to 1 V
Normal: 1 V Less than (0˚ position)
V isual inspection PCB: connection/breakage of wires and/or burn marks on
the computer board.
Error Code
External fan motor failure
681
1 Check whether the external fan motor connected to central computer board
works properly.
Malfunction description
Malfunction description
Malfunction description
Malfunction description
T-M50 / T-M50 ASME Service manual
Turn off the power
Diagnosis
Turn off the power or water supply
Diagnosis
Turn off the power or water supply
Diagnosis
Turn off the power
Diagnosis
44
CONFIDENTIAL
Ver. 1.05
Cancellation method
Checkpoint
Cancellation method
Checkpoint
Cancellation method
Checkpoint
Cancellation method
Checkpoint
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