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WM GV90+ Backfiring

jedic97 Member Posts: 1
I would have a question on my fairly recently installed (2 years operating) WM GV90+ baseboard heating system, as it would somewhat frequently "Backfire" with an compressive slam to the system. This did not happen, that I had noticed, at all the first year; but now it seems to be happening probably a few times a day. I had checked the exhaust line, which has a grate with no blocking debris. And there is no blockage of the intake which does draw significantly.

I would say the exhaust pipe (6" pvc) is at least 10-12 ft to the exterior wall, and another 8 ft outside with a 60 deg downturn.

I will likely get this looked at, but wanted to hear the word on the street if these wer having ignition issues.

Otherwise Im not fond of the cycling timing of the circulators. I believe that they do not stay on long enough or at all after the call to heat is satisfied.




  • Tim McElwain
    Tim McElwain Member Posts: 4,480
    Has it been

    cleaned and serviced since it was installed? Has a combustion analysis been done?

    Are there any lights flashing on the United Technology 1013-200 control?