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Munchkin E-13 Code

JUGHNE Member Posts: 10,898
I was servicing a 2003 199,000 BTUH Munchkin today.
Was getting F09 codes, cleaned HXC, spark and FS.
Several good starts and light offs. FS showed 4.1 microamp at 4600 RPM. No F09 codes.
Changed high limit from 160 to 155.....then:
Would not restart, showed first F-13 and then E-13.....low fan speed.
Fan would not run at all. Reset did nothing...Power off and back on did not change anything.
Unplugged control cable and with 120 at power cable to fan, fan would not go to high speed.
(I think this should happen??).
Returned HL back to 160 and still E-13.
Did the fan just decide to die while I was there?

This boiler has done well since install, only needing cleaning every 2 years and perhaps a FS and spark electrode.
No major parts other than that.


  • HomerJSmith
    HomerJSmith Member Posts: 2,309
    F13: The Fan is running too Stow. Check the wiring of the blower. Check the rpms of the blower. The series A 199M-'s-polarity could be the reason, Older blowers, series A, with a non molex connection should not bc used, with series B, C, & D 925 controls. Usually, this means the blower needs to be replaced. However, check the termination for exhaust air recirculating back into the intakeair. Check the boiler's exhaust connections in the boiler cabinet for leaks-and all PVC joints in and around boiler for exhaust leaks. Look for signs of moisture such as rusting of the gas piping and corrosion/pitting of the aluminum surfaces within the cabinet. Also check proximity of the Munchkin's intake air termination with 'other appliances, such as clothes dryers, range hoods, other heaters. Recirculated & moisture exhaust the boiler intake air will destroy the blower and the
    next blower if not remedied,
  • Also check the venturi and swirl plate.

    Yes, I think you're right, i.e. unplugging the control cable will cause the fan to go to high speed.

    I'd replace the fan and the control board if it's not already a 926 (black transformer) board.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • HomerJSmith
    HomerJSmith Member Posts: 2,309
    edited November 2019
    As you know, an E Code is a warning code that a fault code is about to be displayed if not corrected in 1 min.

    I guess it is a 2013 year model?
    JUGHNE Member Posts: 10,898
    Got a replacement fan. Did "bench test" with the existing boiler cables. Motor took right off and ran.
    The 4 Allen head SS screws were a battle to remove. Seems they galled them selves into the AL housing. Every 1/4 turn seemed like it was twist off time. WD 40 applied. After out they would go back in with fingers.

    Lights off as needed now. This does have the "red" transformer on the control panel.
    What is the advantage of changing the control board to the "black" transformer design??

    This is a 2003 boiler. The inlet and exhaust are at least 4-5' apart.
  • Timco
    Timco Member Posts: 3,040
    The red transformer means 925 control. The black transformer is 926 control and requires the entire upgrade kit with board, display, and cables. Please feel free to call me direct at 774-271-3176 with any questions or concerns after 8am EST for help if needed. Tim White
    Just a guy running some pipes.
  • Removing and reinstalling those screws is the hardest part of changing the fan.

    The 926 control has some changes; longer pre-purge and post-purge times. Tim: Can you tell us what other changes there are?

    The older board will also throw out erroneous error messages.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    JUGHNE Member Posts: 10,898
    After getting those screws out, each one was run in and out of each hole. With WD-40 for lube and cleaning. They then would go in by fingers. Must have cut the galling substance out of the threads.

    Since 2003 install the only codes for lock out were: F-09, which cleaning corrected; F-13 when the fan died.

    FYI, I have a KBN 080 in my basement which would lock out on low fan speed. It seems to have been caused by erratic end switch on a HW zone valve. It would close long enough to start the pre-purge, then open for a split second and back on again.
    Seems this start-stop-start may have confused the board long enough to lock out. I was lucky enough to notice this and not get into throwing the parts at it.

    The end switch was replaced 30 days ago, the new parts of fan and board sit next to the boiler in my basement.........as soon as I return them there will probable be a lock out again :(

    Also FWIW, unplugging the control cable while the 120 VAC cable is energized would cause the fan to ramp up to high speed.