Munchkin Gas-Fired Hot Water Circulating Heater installation manual Part 14 Troubleshooting

GAS-FIRED HEATER Installation Manual

PART 14: TROUBLESHOOTING (CONTINUED)

Table 14-2: 925 Control Board FAULT Codes

Code	Description		Remedy
		1.	Check circulation pump operation
„		2.	Assure that there is adequate flow through the heater by accessing the
	High Limit Exceeded.		status menu and assuring that there is less than a 50°F rise from the
F00
			return thermister to the supply thermister.
		3.	Check thermister reading on supply thermister. Replace switch if faulty.
	Vent Temperature Limit Switch	1.	Push the red reset button on the vent temperature limit switch.
F01		2.	Check the flue temperature during operation using a combustion analyzer.
	Exceeded.
„		3.	Replace the vent limit switch if faulty.
F02	Interrupted or Shorted	1.	Check the electrical connection to the thermister on the outlet manifold.
„	Supply (Outlet) Thermister.	2.	Replace thermister if necessary.
F03	Interrupted or Shorted	1.	Check the electrical connection to the thermister on the inlet manifold.
„	Return (Inlet) Thermister.	2.	Replace thermister if necessary.
		1.	Check circulation pump operation.
F05	Supply (Outlet)	2.	Assure that there is adequate flow through the heater by accessing the
„	Temperature exceeds 230°F.		status menu and assuring that there is less than a 50°F rise from the
			return thermister to the supply thermister.
		1.	Check circulation pump operation.
F06	Return (Inlet) Temperature	2.	Assure that there is adequate flow through the heater by accessing the
„	Exceeded 230°F.		status menu and assuring that there is less than a 50°F rise from the
			return thermister to the supply thermister.
		1.	Watch the igniter through the observation window provided.
	No flame detected – The heater	2.	If there is no spark, check the spark electrode for the proper ¼” gap. Use
			2 quarters together as a gauge to check gap distance.
	will make three attempts at
		3.	Remove any corrosion from the spark electrode and flame rectifier
F09	ignition before the control goes
			probe.
„	into this lockout condition. *See	4.
	spark electrode detail.		If there is a spark but no flame, check the gas supply to the heater.
		5.	If there is a flame, check the flame sensor.
		6.	Check any flue blockage or condensate blocks.
		1.	Monitor the gas pressure to the unit while in operation.
		2.	Assure that the flame is stable when lit.
	Loss of Flame Signal – The heater	3.	Check to see if the green light on the display module is out while the
F10	will relight 4 times before the		heater is running.
„	control goes into this lockout	4.	If the green light doesn’t come on or goes off during operation check the
	condition.		flame signal on the status menu.
		5.	If the signal reads less than 1 microampere, clean the flame rectifier probe.
		6.	If the flame rectifier probe continues to read low, replace it.
		1.	Turn the gas off to the unit at the service valve.
	False Flame Signal – The heater	2.	If the flame signal is still present replace the igniter.
		3.	If the flame signal is not present after turning off the gas supply, check
	will lock out if it senses a flame
F11			the gas valve electrical connection.
	signal when there should be none
„		4.	If there is no power to the gas valve, remove the valve and check for
	present.
			obstruction in the valve seat or replace the gas valve.
		5.	Turn the gas on at the service valve after corrective action is taken.
	Combustion Fan Speed Low – The
	heater will lock out if it senses that	1.	Check the combustion air fan wiring.
F13	the fan speed is less than 70% of	2.	Replace the combustion air fan.
„	expected rate for more than 60	3.	Replace the control board.
	seconds.
	Combustion Fan Speed High – The	1.	Check the combustion air fan wiring.
F14	heater will lock out if the fan speed	2.	Replace the combustion air fan.
	is more than 130% of expected
„		3.	Replace the control board.
	rate for more than 60 seconds.
		1.	Make sure the connector is correctly connected to the gas valve.
F18	Gas Valve Error	2.	Check the electrical wiring from the valve to the control board.
		3.	Replace the low voltage wiring harness assembly.
„
		4.	Replace control board.
„	Watchdog	Call factory for further assistance.
F30
„	Parameter Memory	Call factory for further assistance.
F31
„	Parameter Memory Write Error	Call factory for further assistance.
F32
„	Programming Error	Call factory for further assistance.
F33
			60