Fan Motor For Exhaust - A.O. Smith T-H2-DV Service Manual

10-4. Fan motor for exhaust

Unit Part #
Function
Failure events
Effects on the water
heater if fan motor for
exhaust fails
Error codes when the fan
motor fails
Diagnostic
Color/Number of wires
The fan motor for exhaust of the
T-H2-DV has the "46" mark as
shown the picture to the right.
#124 Takagi Part #
To control exhaust temperature.
1. Fan speed failure, causing abnormal sounds with or without combustion
during operation.
2. Unexpected activation caused by the connectors of the fan motor getting
wet.
3. Disconnects from the exhaust chamber.
1. The water heater does not function properly
2. Unstable exhaust gas temperature
621 (T-H2-DV only)
1. Visual inspection: connection/breakage of wires or dust (causing electrical
shortage)
2. Voltage check: proper range of voltages shown below.
Red-Blue 110 to 160 VDC (Input)
Yellow-Blue 13 to 17 VDC (Input)
Orange-Blue 2.0 to 6.5 VDC (Input)
Verify the fan motor speed for exhaust using the
Diagnostics Mode of the T-H2-DV computer board or the
White-Blue
TM-RE30 temperature remote controller. See Section 12-1
for details.
T-H2-DV/T-H2-OS Service Manual
EKH5T
22
CONFIDENTIAL
Ver. 1.01
Checkpoint
941 (T-H2-DV only)
G2