T-M50 / T-M50 ASME Service manual
Ver. 1.05
42
CONFIDENTIAL
Error Code
Malfunction description
Cancellation method
Disconnected AFR rod
Turn off the power or water supply
Diagnosis
Checkpoint
391
1 AFR rod fault
(Refer to section 10-6)
Visual inspection: connection/breakage of wires, soot on it.
I
Error Code
Malfunction description
Cancellation method
Flow sensor failure
Turn off the power or water supply
Diagnosis
Checkpoint
441
1 Flow sensor failure
(Refer to section 10-9)
Visual inspection: connection/breakage of wires and/or debris on impeller.
Check voltage/resistance between (red & black) or (white & black)
H2
Error Code
Malfunction description
Cancellation method
Fault of driving circuit for main gas solenoid
valve (MV)
(The computer checks the condition of the main
gas valve immediately after every operation)
Turn off the power supply
Diagnosis
Checkpoint
510
1 Left and/or Right PCB and/or main gas valve fault
(Refer to section 10-4 & 10-14)
Visual inspection of gas valves: connection/breakage of wires.
Normal: 78 to 100 VDC between COM (blue) & #3 (light blue)
(during operation)
Visual inspection of PCB: connection/breakage of wires and/or burn marks
on the computer board.
2 Main gas valve fault
C
