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Weil-McLain GV-4 won't fire

Cruisinfanatic Member Posts: 28
I have a Weil-McLain GV-4 series 1 that won't go past fan running with only the power light lighting.
After a few recycles, I did get it to light and heat for about 15 minutes, then it shut down again. Purge light began to flash.
Made an inquiry at the local heating supply store and they suspected leaking air pressure switch supply lines. I left it alone with power off for a day. Came back, flipped the power and has been fine for a few days now.
Does this sound like air pressure switch and, or vac lines?
Maybe replace the switch and the lines?


  • Tim McElwain
    Tim McElwain Member Posts: 4,506
    Do you have the manuals on the GV4? If so there is a section on testing pressure switch and also diagnosing flashing lights.
  • Firecontrol933
    Firecontrol933 Member Posts: 73
    Check your venting to make sure nothing has gotten in there.

    Also, does the blower sound "normal"? I've seen a few of the wheels come apart which makes a noise and vibration that's hard to miss.

    Make sure that the drain is clear.

  • Cruisinfanatic
    Cruisinfanatic Member Posts: 28
    I'll check those things. Looks like the switch is readily available. What about the vac lines. Anything special about them to replace?