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Opening EFFICAL vent damper.

I have an EFFICAL vent damper on a gas boiler. I am trying to light the boiler. When I move the switch to the "hold open damper" position, the damper does not move. I tried twisting it by hand, but it is too stiff. Any suggestions?


  • Steamhead
    Steamhead Member Posts: 16,723
    That damper is supposed to work automatically. If you twist it, you may damage the motor assembly.

    If the boiler doesn't start, you need to call a pro. Where are you located?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    HVACNUT Member Posts: 5,740
    The switch on the damper motor is to leave the damper open once its already open. Dont force it. Is there 24v at the motor?