A.O. Smith T-D2-OS Service Manual page 43

Error Code
Fan motor fault
611
1 PCB and fan motor fault
V isual inspection of fan motor: connection/breakage of wires or dust
buildup (causing electrical shortage)
Normal: 110 to 160 VDC between red & blue (during operation)
Normal: 13 to 17 VDC between yellow & blue (during operation)
Normal: 2.0 to 6.5 VDC between orange & blue (during operation)
Verify fan motor speed of the water heater using the "diagnostics mode" of
the TM-RE30 temperature remote controller. See the "12-1. How to
diagnose the water heater using the TM-RE30".
V isual inspection of PCB: connection/breakage of wires and/or burn marks
on the computer board.
Error Code
Flow adjustment valve fault
(Only Easy-link system)
651
1 PCB and flow adjustment valve fault
(Refer to section 10-8 & 10-15)
V isual inspection of flow adjustment valve: connection/breakage of wires,
motor drive locked due to scale buildup, and/or water leakage.
Normal: 7 to 16 VDC between (black-red)
V isual inspection PCB: connection/breakage of wires and/or burn marks on
the computer board.
Malfunction description
(Refer to section 10-3 & 10-15)
Malfunction description
T-D2-IN / T-D2-OS Service Manual
Turn off the power or water supply
Diagnosis
Turn off the power or water supply
Diagnosis
43
CONFIDENTIAL
Ver. 1.00
Cancellation method
Checkpoint
Cancellation method
Checkpoint
G
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