Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Frustrated plumber GV-6 keeps dropping flame

Dave101 Member Posts: 1
Have a GV-6 series 2 that keeps dropping flame signal and locking out, runs great for 2-3 cycles then drops flame signal, I’m on 3rd igniter, ohm reading on igniter is 48.8, I have cleaned the burner, the squirrel cage and the ecm is less than a year old.... does ANYONE have an idea why it just randomly drops the flame? When it locks out pres switch light is out and flame light is blinking. I shut power off it will make it through 2-3 cycles and drop signal again.


  • Ironman
    Ironman Member Posts: 7,119
    edited September 2019
    Has a combustion analysis been done? What's the manifold pressure? LP or natural?

    Have you checked the ground connections all the way back to the electric panel?

    Is the flue clear of any obstructions? Is the condensate drain clear?
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Docfletcher
    Docfletcher Member Posts: 483
    I'm not a pro, but I know for sure that If the inducer fan connector on the control board is not making a solid connection it may open up intermitently and cause a shutdown.
  • Tim McElwain
    Tim McElwain Member Posts: 4,588
    Do you have the I & O manual for the GV? If so look in the troubleshooting section for proper diagnosis. What is happening with the lights on the Integrated Boiler Control? What are you getting for microamps? Which United Tech board do you have on the unit? I would say that if the pressure switch light is out then you are not getting correct differential pressure across the switch you need to check the pressure with a digitial manometer.
  • Tim McElwain
    Tim McElwain Member Posts: 4,588
    Check switch pressure setting
    1. See Figure 27.
    2. Remove both air pressure switch hoses from air pressure switch.
    3. Install tees and tubing as shown in Figure 27 to inclined
    4. Turn off gas valve and set thermostat to call for heat. Blower will run but burner will not ignite.
    5. Check for 24 VAC between both air pressure switch terminals and ground.
    6. If manometer reading is at least 1.4" W.C., but there is not 24 V AC between both air pressure switch terminals and ground,
    replace air pressure switch.

    Troubleshooting air pressure reading
    1. If manometer reading is lower than 1.4" W.C. check for possible causes:
    • blockage in hoses.
    • loose blower wheel on motor shaft.
    • blower motor not at proper rpm.
    • blockage in air inlet or hose.
    • blockage in flue pipe or termination.
    • condensate trap filled w/condensate.
  • Tim McElwain
    Tim McElwain Member Posts: 4,588

  • Docfletcher
    Docfletcher Member Posts: 483
    If memory serves me the pressure switch light is out after shut down is normal. If both the power light and pressure switch light are blinking then the pressure switch failed to close. Ensure you do not have an obstruction in your venting. I'm not a pro.
  • johnlemen
    johnlemen Member Posts: 5
    dave, weil-mclain put out a (rev 1) tech service bulletin feb 25, 2004 for model gv boilers series 1 & 2. it is #sb0401r1. i have gone thru this w/boiler contractors over the years. your can also call weil-mclain tech @ 1-800-654-2109 option 2.
  • Tim McElwain
    Tim McElwain Member Posts: 4,588

    That Bulletin has to do with Mixing Valves on the older GV series. I do not believe that is the problem here.