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GV90+ Weil McClain boiler suddenly won't heat water, Arctic freeze coming

jeffpas Member Posts: 1
Going to be -14 below tomorrow night and -13 the next, a couple days of arctic freeze. Should be in the 50s by the end of the week however.
But until then, I'm in trouble.

The GV90+ Weil McClain boiler that came with the house I acquired a couple months ago- less than 5 years old and looking relatively new- suddenly stopped working.
The boiler fires up every 15 minutes or so, and there is a bit of a voomk sound a couple times and water circulating. But the radiators in the house remain all ice cold.
What could possibly have happened?

My thought is perhaps the pump is not starting, and that is the noise? However there is also a bypass pump right there, side by side. Is there a way perhaps, to engage the bypass as a failsafe?
I can't help but think the problem is something simple, but the solution escapes me completely. The panel says 140.... and the POWER light is blinking green, with a couple other lights blinking red- TSTAT, PRESS SWITCH and FLAME, all blinking red. The LIMIT light is solid red.

The manual reads like a surgeons manual, I can't figure out for anything what the problem could be.
If anything, I'd like to know how to drain the boiler and turn it off for the deep freeze, so the radiators don't break. I have some electric heaters in the house but I fear that won't be enough when temps get that low soon.
Thanks for any help or experience.


  • Gordy
    Gordy Member Posts: 9,546
    Page 89 of the manual has what the lights mean for trouble shooting.
  • Jellis
    Jellis Member Posts: 228
    hello Jeff, it sounds like you have just a single zone in this home? Some pictures of your system would be helpful to try to narrow down your problem, and to assist with draining if need be.

    if you "hear" the water circulating than it is likely you have air in your loop and it needs to be purged, this could be the reason for no heat.
    Your circulator could be bad you may find your motor very hot to the touch but not actually moving water through the system.

    JUGHNE Member Posts: 11,086
    Is it possible you already have some heating pipes frozen on the out side walls?
    Trying to drain all the water out of the system might be difficult if not impossible.
    First thing is to look at the exhaust and inlet ports outside. They could be frosted over.

    If ports look clear, you should probably call for a pro.
    Was there any home warranty coverage when brought the house......might be days of waiting if you go that route though.

    Pictures of pumps.
    EBEBRATT-Ed Member Posts: 15,721
    wore comes to worse run you electric heat and get an extension cord and wire the circ pump to it and plug it in. Moving water is less likely to freeze.

    That's a last resort try and get a professional