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Weil-McLain GV-4 won't fire
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?