A.O. Smith 110 Indoor Service Manual page 40

Error Code
12
5 Disconnected/damaged O.H.C.F.
V isual inspection: connection/breakage of wires.
Error code is
Normal: 1 Ω or less between blue & blue
shown after
6 Check if hi-limit switch is properly functioning.
three failed
7 Disconnected/damaged hi-limit switch. (Refer to section 10-11)
attempts at
V isual inspection: connection/breakage of wires.
Normal: 1 Ω or less between blue & blue
ignition
Error Code
Disconnected/short-circuited outlet thermistor
31
1 Outlet thermistor fault
V isual inspection: connection/breakage of wires and/or debris on
thermistor.
Check voltage/resistance between black & black (#113).
Refer to Section 8 for proper range of values.
Error Code
Disconnected/short-circuited inlet thermistor
32
1 Inlet thermistor fault
V isual inspection: connection/breakage of wires and/or debris on
thermistor.
Check voltage/resistance between black & black (#42).
Refer to Section 8 for proper range of values.
Error Code
Disconnected AFR rod
39
1 AFR rod fault
V isual inspection: connection/breakage of wires, soot on it.
Malfunction description
Malfunction description
Malfunction description
110 Indoor / 110 Outdoor Service Manual
Diagnosis
(Refer to section 10-12)
Turn off the power or water supply
Diagnosis
(Refer to section 10-10)
Turn off the power or water supply
Diagnosis
(Refer to section 10-10)
Turn off the power or water supply
Diagnosis
(Refer to section 10-6)
40
CONFIDENTIAL
Ver. 1.01
Checkpoint
Cancellation method
Checkpoint
Cancellation method
Checkpoint
Cancellation method
Checkpoint
C2
C1
E1
E2
I