andrews Fastflo WHC56 Service Manual page 30

7. Gas solenoid valve error.
8. Fan motor error.
9. Combustion fan speed sensor error.
If error display 11 appears and there is continuous
electrical discharge, then check the gas solenoid
valves.
(1) Open the hot-water supply valve and measure
the voltages between:
SV0: White 6 and Blue 7 on connector 10
SV1: Black 5 and Blue 7 on connector 10.
DC 80 - 100V
Normal
Yes Replace the bad gas solenoid valve.
No Replace the circuit board.
If error display 61 appears, then check the fan
motor.
(1) Measure the voltage between Blue 2 and
Brown 4 of connector 27 on the circuit board.
DC 7 - 48V
Normal
Yes Replace the fan motor.
No Continue to "9. Combustion fan ...".
If error display 61 appears and the fan is rotating,
then check the fan speed sensor.
(1) Measure the pulses between Yellow 3 and
Red 4 of connector 102 on the circuit board.
• Check to see if maintenance infomation monitor
no. 10 (fan speed) and no. 20 (set fan speed) are
close when the maximum pressure or minimum
pressure set button are pressed (don't press
button during ignition).
Normal 150 - 400 Hz (4 pulses/rev.).
Yes Replace the circuit board.
No Replace the combustion fan.
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