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OK to remove dead auto damper from flue?

Hello all---

I'm a homeowner, and trying to be extra cautious about proper venting so I hope I'm not asking a dumb question.

I have a standing pilot, nat gas boiler, atmospheric vent--- with an autodamper on the stack.

The autodamper has failed frequently....either getting stuck or having the motor poop out.

The contractor replaced it several times and finally gave up, and permanently disabled it by pulling the activation wiring. However, it is still installed in the flue above the draft hood, obviously permanently in "open" position.

It would be very easy for me to remove and I would like to do that to eliminate any risk (very small, of course) of activating it somehow. It made no disernable difference in efficiency anyways even when it did work.

I also imagine it might (in a very limited manner) improve draft a bit to have it gone.

Any reason that would not be safe? The flue is singlewall 5" vent, and I would probably just replace the whole section of vent to eliminate a joint. Am I right it would marginally improve draft too?

thank you for any expert advice offered, I appreciate it.


  • Slimpickins
    Slimpickins Member Posts: 330
    why not

    Its not harming anything still in place but if you do replace the single wall, use 26 gauge pipe, not the flimsy stuff you can buy at Home Cheapo. Use 3 zip screws equal distance around the pipe to secure and you're done. 
  • Tim McElwain
    Tim McElwain Member Posts: 4,580
    I recommend when

    you have a professional remove the damper that you also have the jumped out primary control replaced.
  • Tim

    From what I get he had all the wiring removed(in the OPEN position),,, so removing the VD would not be

    "brain surgery",,, c`mon give us a break!
  • Tim McElwain
    Tim McElwain Member Posts: 4,580
    All primary controls used with

    vent dampers have an internal fuse which blows on the first call for heat, after that the unit will not fire without the damper attached or a jumper placed across the vent damper connector terminal on the primary control. When the damper is actually removed and replaced then the jumper is removed and the new damper plugged in. The jumper is not allowed to be a permanent fix therefore a new control should be installed if a new damper is not going to be installed. Big time liability involved! Weil McLain is one of the manufacturers which has a factory bulletin on this procedure.
  • Al Letellier_21
    Al Letellier_21 Member Posts: 402
    removing flue damper

    Tim: Thank youfor being on the ball and educating the industry, especially on that very special word......liability !!!  In my insurance investigation work, it simply amazes me how many in our trade simply don't care or have a clue about exposure to liability. When I interview techs about what they did, I so often here "HUH ????" when I tell them of the dangers of altering equipment from factory specifications...they simply don't understand how they are exposing themselves to extensive liability and law suits.

    It's about time this industry wakes up to the dangers of a supposed trained industry technician becoming a "do-it-yourselfer". It is simply dangerous to think you can outthink the manufacturer and its team of R&D people.
  • Tim McElwain
    Tim McElwain Member Posts: 4,580
    Al, I take time in all my classes

    to alert techs to the liability issue with certain types of frequent behavior that seems to be acceptable but is actually leaving them wide open for a law suit. When we "change the design" on equipment there has to be as numerous judges I have been involved with as an expert witness ask me "Is this a long standing practice in the industry" and then they ask "Mr expert witness do you have documentation to support this long standing practice". Some of the documents I have on file for support of different gas practices are as much as 50 to 60 years old and I have used them often to get a company or tech off the hook. Problem many times is the company policy does not have any support for these actions. Often times the techs are what I call "loose cannons" just waiting to fire of in any direction.

    I have over the years found limits jumped out, controls with the insides removed, garden hose connecting gas equipment, do not even get me started on the many venting violations, lack of air for combustion. Incorrect parts installed on equipment, and the list goes on.
  • Slimpickins
    Slimpickins Member Posts: 330
    Gotta responde to this

    Tim and Al both made it seem like I gave bad advice on physically removing the vent damper. The OP said his contractor pulled the wiring and he didn't say anything about jumping the connector. It seemed like the OP had his mind made up that he was going to remove it and replace with vent pipe regardless so I gave advice.

    I've been in the field many years running service and have removed many a molex connector to a faulty vent damper and jumped the connector to get customers heat in frigid conditions. I don't lose any sleep over doing this because the worse case scenario is if the jumper is removed or falls, out the boiler won't fire. Also I NEVER tell the customer that this is an accepted repair and only temporary, after all we're in this to make money and make people safe.  I am well aware of liability and always put in writing on the invoice that I've jumped the control and either the vent damper or the control must be replaced with the vent damper removed. Out of a dozen or so, I think I've had one customer follow up and done the recommended repairs.  In my jurisdiction there is no mechanism to force the customer to make a repair.  I would NEVER EVER jump a safety or limit switch and leave and return with the part later.

    Maybe I should have asked the OP more details but from what I read, it seemed like harmless advice. He said he already had the contractor over several times so I assumed he did the right thing with the control. He probably gave a price to remove the damper and the OP declined thinking he could do it himself. After all, it's not brain surgery as Dave eloquently said.

    Thanks for being concerned about safety with vent dampers, it is one of the things that can seriously danger lives.

This discussion has been closed.