Announcement Announcement Module
Collapse
No announcement yet.
Goodman gas furnace failed to ignight burner fyi Page Title Module
Move Remove Collapse
X
Conversation Detail Module
Collapse
  • Filter
  • Time
  • Show
Clear All
new posts

  • Goodman gas furnace failed to ignight burner fyi


    customer complained house 60 degrees and furnace doing nothing. I asked if she had gas kitchen stove, lit 4 burners, great flame so no pressure problems.

    Gas furnace vertical, 3 gas burners 70k btu, with glow bar ignition first burner, ignition sensor on 3rd burner. First burner came on 2 seconds when glow bar got cherry red then gas valve shut off by computer board because sensor did not detect flame in third burner. Second and third burner failed to ignite.

    I replaced sensor, igniter, and gas valve....same thing. So i replaced pc board same thing.

    I had to mark all 3 burners so they could be reinstalled in same order. Removed burners, used very thin putty knife to clean burner pilot slots, wire brushed them and also the burner nozzles, used plastic tie to make sure no obstructions in pilot slots, and blew out with compressed air. Removed orifices and blew them out. Put everything back together and it all worked great. Hope this helps someone in the future with the same problem. Note: Be very careful of the glow bar igniter it will break "extremely " easy and it is a show stopper if no body is open (holiday or weekend) to sell you a new one.

    Don't forget to bubble test all gas joints when finished.

  • #2
    Re: Goodman gas furnace failed to ignight burner fyi

    orifices, cross lighters, and flame sensors are very common areas of failure due to lack of maintenance, especially if the fuel is LP.

    cherry-red is not hot enough to reliably light off a gas fuel. the igniter, whether carbide or nitride needs to be yellow/white hot. if it's anything else, dull orange/red, there's a problem someplace. a carbide hot surface igniter is very fragile. they are usually the M or curly round style. Nitride is a very hard material that is difficult to break with force. It is usually a rectangular bar or a slotted cylinder in shape.

    nitride and carbide can usually be interchanged BUT only if the igniter voltage is above 100 volts. Anything less and nitride will not reliably ignite fuels. a true RMS meter can tell you igniter voltage, a regular meter may lie due to a non-true sine wave frequency.

    testing fuel pressure by stove activation is not a reliable test. only a manometer during furnace firing will tell you if you have proper pressure and volume. modern in-shot burners needn't be numbered or installed in the same order. that applied to old ribbon burners if they didn't have combustion air adjusters and if the tech didn't know how to adjust them. after all, replacement in-shot burners just come in a box with no specific order of installation.

    a full clean and check should have been the first thing to do after your diagnostics. parts changing should come later, if needed. your manometer and volt meter, both inexpensive tools, are your best diagnostic friends.

    what exactly did the customer get charged for? parts and labor? all the time? some of the time?
    ~~

    ... it was plumbed by Ray Charles and his helper Stevie Wonder

    Comment


    • #3
      Re: Goodman gas furnace failed to ignight burner fyi

      Originally posted by cei955 View Post
      customer complained house 60 degrees and furnace doing nothing. I asked if she had gas kitchen stove, lit 4 burners, great flame so no pressure problems.

      Gas furnace vertical, 3 gas burners 70k btu, with glow bar ignition first burner, ignition sensor on 3rd burner. First burner came on 2 seconds when glow bar got cherry red then gas valve shut off by computer board because sensor did not detect flame in third burner. Second and third burner failed to ignite.

      I replaced sensor, igniter, and gas valve....same thing. So i replaced pc board same thing.

      I had to mark all 3 burners so they could be reinstalled in same order. Removed burners, used very thin putty knife to clean burner pilot slots, wire brushed them and also the burner nozzles, used plastic tie to make sure no obstructions in pilot slots, and blew out with compressed air. Removed orifices and blew them out. Put everything back together and it all worked great. Hope this helps someone in the future with the same problem. Note: Be very careful of the glow bar igniter it will break "extremely " easy and it is a show stopper if no body is open (holiday or weekend) to sell you a new one.

      Don't forget to bubble test all gas joints when finished.

      Why did you replace the Sensor, Igniter and Gas valve ??? When all of it was testable and appeared to work by your description.... Sounds like a bad case of parts swapping to me...

      Why on earth would you not check the burner orifi if 1out of three burners are lighting off first???

      While I appreciate the advice, May I offer you some? Look into your local RSES chapter Deprecated Browser Error they offer great continuing education and troubleshooting classes...

      P.S> Plumber Punky is spot on as well...

      Comment

      Working...
      X