A.O. Smith T-H2-DV User Manual

T-H2-DV/T-H2-OS Service Manual
Ver. 1.01
53
CONFIDENTIAL
Error Code
Malfunction description Cancellation method
711
1.
Hi
-
limit switch trip
/
Overheat cutoff fuse compromised
NOTE: When these components are compromised,
the “711” error code may appear instead of
the
“
111
”
or
“
12
1
”
error codes.
Turn off the power supply
2.
Driving circuit fault for gas solenoid valve (VG
0
)
Diagnosis Checkpoint
1(A) Hi-limit switch trips (Refer to section 10-14)
Visual insplection: connection/breakage of wires.
Normal: Less than 1 Ω between blue & blue
C1
1(B) Overheat cutoff fuse compromised (Refer to section 10-16)
Visual inspection: connection/breakage of wires.
Normal: Less than 1 Ω between blue & blue
C2
2 PCB and/or gas valve fault (Refer to section 10-5 & 10-18)
Visual inspection PCB: connection/breakage of wires and/or burn
makes on the computer board.
C
Error Code
Malfunction description Cancellation method
721
False flame detection
Turn off
the power or water supply
Diagnosis Checkpoint
1 False flame detection (5 sec.)
Flame rod (Insulated resistance) fault
I
Error Code
Malfunction description Cancellation method
741
Miscommunication between water heater and
temperature remote controller
Restoring proper cable connections
between the water heater and the
Remote controller (TM-RE30). When the
computer detects proper connections
between the water heater and the
remote controller, "741" error code will
cease to display.
Diagnosis Checkpoint
1 Temperature remote controller (TM-RE30) or PCB fault
2 Check for signs of power surges.

A.O. Smith T-H2-DV Specifications

General

Brand	A.O. Smith
Model	T-H2-DV
Category	Water Heater
Language	English