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What does this vent damper do and should I use it. I have it on hold open

acl10
acl10 Member Posts: 349



Comments

  • Neild5
    Neild5 Member Posts: 170
    It closes the flue when the burner is not on, this stops heated air from going up the chimney.
    acl10
  • Jamie Hall
    Jamie Hall Member Posts: 23,986
    What on earth is that thing attached to? What it is is a powered damper, which is supposed to close when the appliance to which it is attached isn't operating. The idea is that there will be a call for the appliance to operate, and it is supposed to open and then -- and only then -- is the appliance allowed to fire up.

    The idea is to reduce or eliminate heat loss up the stack when the appliance isn't operating. If it is operating properly, it will do just that. If it isn't, the appliance won't operate -- and they have proven to be somewhat problematic contraptions.

    It should do no harm if it is locked open so the appliance can operate -- except for the loss of some warmer air up the stack.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • New England SteamWorks
    New England SteamWorks Member Posts: 1,521
    Common for them to fail. No harm in manually wedging it open.
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
    newenglandsteamworks.com
  • acl10
    acl10 Member Posts: 349
    Thats the chimney pipe going to the brick chimney
  • Steamhead
    Steamhead Member Posts: 17,177
    They've gotten better over the years. We stock replacement motors for them.

    On older chimneys, say pre- World War 2, they can make a significant difference. These older chimneys were built to pull air through coal beds in the original boilers, so they can almost pull pets and small children up to the roof. Such a draft can cool a boiler down quickly, but with the damper closed that can't happen.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
    Double DratioCanucker
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,578
    @Steamhead Pets and small children!!! HAHAHAHA.
    Retired and loving it.
    Neild5SuperTech
  • Reinvent
    Reinvent Member Posts: 43
    Can they be used on an oil fired steam system?
    Also I have an electronic LWC that shuts the boiler down for 1 min every 20 min during operation to check the level. Could the motorized damper be put on a 2 min delay so it does not get unnecessarily abused?
  • Steamhead
    Steamhead Member Posts: 17,177
    edited January 2018
    That model is designed for gas. But Field does make one for oil-fired units- the OVD series. Go here:

    http://www.fieldcontrols.com/oil-vent-damper?page_id=409

    Not sure what boiler you have, but if the stack damper is wired after the low-water cutoff it'll do that as a matter of course.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • mikeg2015
    mikeg2015 Member Posts: 1,194
    Steamhead said:

    They've gotten better over the years. We stock replacement motors for them.

    On older chimneys, say pre- World War 2, they can make a significant difference. These older chimneys were built to pull air through coal beds in the original boilers, so they can almost pull pets and small children up to the roof. Such a draft can cool a boiler down quickly, but with the damper closed that can't happen.

    Your not kidding. I’ve been measuring the draft and I’ve added a manual damper and have it more than 1/2 closed. Still have 0.03”. Before I added the draft damper even with the boiler off if the sun was heating the exposed section of chimney in summe it had a hell of a draft. Traps in the basement were almost sucking dry.