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Damper and Backdraft

BLD Member Posts: 2

Our old slant fin has served us well on super cold days (we fire it up to assist our wood stove) and on spring and fall days when you just need to bring the house up to temp first thing in the morning.

Having two problems: 1. We fight a backdraft problem about 50% of the time. I have various unsafe ways to overcome it and force the gases up the pipe and off she goes (no more spillage from the draft hood area). Other times (with me watching it), it will spill for about 30 - 45 seconds and then overcome it on its own. (no one runs the boiler but me). It seems as if its always the first fire, never does it again when it is cycling on and off.

2nd issue: This season I noticed that my damper is not closing upon shutdown. Because we dont run the boiler much, I decided to close off all that cold air coming in the basement and went and closed it manually. Then I forgot and turned on the thermostat one morning, heard the loud click that always happens at call for heat and went running for my pliers to open the flue. But it was just finishing opening when I got there. Through multiple tests, it's confirmed it will open every time, but never closes automatically (just manual).

Any thoughts on these two issues would be greatly appreciated!!


  • Big Ed_4
    Big Ed_4 Member Posts: 2,827

    The draft problem seems to be a cold chimney from just firing the boiler up now and then . Replace the damper motor . And reopen the air intake which is very important .

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  • BLD
    BLD Member Posts: 2

    Thank you Ed! Nice catch on the cold air intake :-) I was hoping there were some relays in that motor that might need cleaned. I'll check into that replacement motor. Thanks again!

  • Steamhead
    Steamhead Member Posts: 17,003

    Part number for the damper motor is GVD-RMA.

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,241

    Are you Certain the chimney is tall enough? Mad