HTP Munchkin High Efficiency Heater - Manual (Page 15)

7-C MUNCHKIN BOILER FAULT LED CODE:
When a fault condition occurs or is sensed on the WHC1100 Munchkin Controller or in the appliance, the control board goes to a LOCKOUTstate.
When in the LOCKOUTstate, the green LED located on the WHC1100 Control board will flash a fault code. The number of times to LED flashes
ON/OFF will determine the nature of the fault (see the table below). To reset the Control from the LOCKOUTstate, remove and re-apply 120VAC
line power to the Control board.
DESCRIPTION of FAULT # of LED PULSES
Limit String Open, Water Pressure Switch, ECO s 2
Flame Stuck ON 3
Ignition Fault (No Flame) 4
Inlet Probe Fault 5
Outlet Probe Fault 6
Air Pressure Switch Fault, Stuck Closed 7
Air Pressure Switch Fault, Stuck Open 8
Redundant Gas Valve Relay Stuck ON 9
Gas Valve Relay Stuck ON 9
Redundant Gas Valve Relay Stuck OFF 10
Gas Valve Relay Stuck OFF 10
Gas Valve wire disconnected 11
ROM Checksum Failure 12
RAM Test Failure 13
60 Hz Failure 14
NOTE:
To read LED flashes 1 flash per second within sets of flashes with
2-second wait periods between sets of flashes. During normal
operation, the LED will pulse continuously.
7-D FAULT CONDITIONS
Limit String Open, High Limit Failure — 2 PULSES
! If the limit string opens, the control will immediately remove power to the gas valve, complete a post purge cycle and enter
a lockout state. To restart the control, make sure that there is at least 10 PSI in the water system, then remove and re-apply
120 VAC line power.
NOTE:
The bi-metallic high limit device must physically close before the
control board will function properly . If a user recycles power to
restart the control and the high limit device is still open, the control
will revert back to the lockout state 2 LED PULSES.
! If the control senses a fault in the limit string, the control will immediately remove power to the gas valve.
After completing a post purge cycle,
the control will go into the lockout state.
Flame Stuck ON — 3 PULSES
! The current state of the flame may be determined by looking through the view port on the combustion chamber. If the flame is stuck ON/OFF
then the flame rod insulator or the connector CN6 may not be clean, or unplugged.
Ignition Failure (No Flame) — 4 PULSES
! If an ignition failure occurs during the trial-for-ignition, the control will return to the pre-purge state and attempt another ignition trial. If after
three trials an ignition failure is still occurring, the control will go into the lockout state. Check that the gas valve is operating correctly and the
plug is fully connected into the valve. Verify that the gas supply is turned on, that there is a proper connection to the 120VAC line source, that
the flame rod is connected and also that the flame rod is clean. Replace the Low-Voltage Cable assembly.
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