Munchkin Gas-Fired Hot Water Circulating Heater - Manual (Page 61)

60
GAS-FIRED HEATER
Installation Manual
PART 14: TROUBLESHOOTING
(CONTINUED)
Table 14-2: 925 Control Board FAULT Codes
Code Description Remedy
„
F00 High Limit Exceeded.
1. Check circulation pump operation
2. Assure that there is adequate flow through the heater by accessing the
status menu and assuring that there is less than a 50°F rise from the
return thermister to the supply thermister.
3. Check thermister reading on supply thermister. Replace switch if faulty.
„
F01
Vent Temperature Limit Switch
Exceeded.
1. Push the red reset button on the vent temperature limit switch.
2. Check the flue temperature during operation using a combustion analyzer.
3. Replace the vent limit switch if faulty.
„
F02
Interrupted or Shorted
Supply (Outlet) Thermister. 1. Check the electrical connection to the thermister on the outlet manifold.
2. Replace thermister if necessary.
„
F03
Interrupted or Shorted
Return (Inlet) Thermister. 1. Check the electrical connection to the thermister on the inlet manifold.
2. Replace thermister if necessary.
„
F05
Supply (Outlet)
Temperature exceeds 230°F.
1. Check circulation pump operation.
2. Assure that there is adequate flow through the heater by accessing the
status menu and assuring that there is less than a 50°F rise from the
return thermister to the supply thermister.
„
F06
Return (Inlet) Temperature
Exceeded 230°F.
1. Check circulation pump operation.
2. Assure that there is adequate flow through the heater by accessing the
status menu and assuring that there is less than a 50°F rise from the
return thermister to the supply thermister.
„
F09
No flame detected – The heater
will make three attempts at
ignition before the control goes
into this lockout condition. *See
spark electrode detail.
1. Watch the igniter through the observation window provided.
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.
3. Remove any corrosion from the spark electrode and flame rectifier
probe.
4. 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.
„
F10
Loss of Flame Signal – The heater
will relight 4 times before the
control goes into this lockout
condition.
1. Monitor the gas pressure to the unit while in operation.
2. Assure that the flame is stable when lit.
3. Check to see if the green light on the display module is out while the
heater is running.
4. If the green light doesn’t come on or goes off during operation check the
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.
„
F11
False Flame Signal – The heater
will lock out if it senses a flame
signal when there should be none
present.
1. Turn the gas off to the unit at the service valve.
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
the gas valve electrical connection.
4. If there is no power to the gas valve, remove the valve and check for
obstruction in the valve seat or replace the gas valve.
5. Turn the gas on at the service valve after corrective action is taken.
„
F13
Combustion Fan Speed Low – The
heater will lock out if it senses that
the fan speed is less than 70% of
expected rate for more than 60
seconds.
1. Check the combustion air fan wiring.
2. Replace the combustion air fan.
3. Replace the control board.
„
F14
Combustion Fan Speed High – The
heater will lock out if the fan speed
is more than 130% of expected
rate for more than 60 seconds.
1. Check the combustion air fan wiring.
2. Replace the combustion air fan.
3. Replace the control board.
„
F18 Gas Valve Error
1. Make sure the connector is correctly connected to the gas valve.
2. Check the electrical wiring from the valve to the control board.
3. Replace the low voltage wiring harness assembly.
4. Replace control board.
„
F30 Watchdog Call factory for further assistance.
„
F31 Parameter Memory Call factory for further assistance.
„
F32 Parameter Memory Write Error Call factory for further assistance.
„
F33 Programming Error Call factory for further assistance.