Pipe & Chimney confusion

I gave you the facts, the damper is not used to control down drafts it is used to control the fire, some chimneys down draft when stove is not in use but not if the chimney is correct, my chimney (two different ones in same house) has never down drafted at any time in 32 years.

Downdrafts can be caused by large objects which are higher that the chimney such as trees and tall buildings located near your home or if your stack isn't high enough in relationship to your roof peak. The wind will blow over the top of these objects and can drop over the the top into your chimney causing downdrafts. Chimney caps help somewhat plus they are a good idea and often required with screens with openings around 3/4" . This will reduce the chance of birds going into your chimney, keep rain out and with proper sized screening should not clog if you're burning dry wood at the right temperature. I did have one occasion where the wind was blowing at the perfect angle that it blew straight down my chimney and cause a major downdraft. Once the chimney gets hot it will reverse and start exhausting.

Ray

I was just telling him for the most part that is NOT what the damper is for.

He thinks down drafts are normal when the stove is not running, that is not the case.

Yes I agree with you Just wanted to add to what you stated

Ray

The physical forces that can cause downdrafts in a cold stove exist in every home, and are not necessarily an indication of chimney problems. The stack effect means that pressure in the bottom floors of a house is lower than the outside, so any air inlet at the bottom of the house is a potential site for air infiltration. A cold stove with air inlets or damper closed will only have minimal path for air to enter so it's not a huge problem. Open your cold stove door sometime, feel the draft? Many do. Maybe not "normal", but common enough.

TE

Well if you have a down draft I think most people would smell it, there has been some report the smell but not a huge number, I stand by my statement, most chimneys are not going to do this, my chimney is not even that tall and it has never done it in 32 years. I just said it was not "normal" to have that situtation.

The damper can be used for whatever you want to use it for, down drafts, up drafts, bats, bugs, rain and extremely small people. The damper is essentially a lid on a container, the container being your chimney pipe. And while you've made it clear that you've not had a down draft in 32 years, I've not had a break-in in a similar span of time, but I still lock my door.

With good burning habits, no creosote, no smell. If you only have wood heat you may not notice either, because the house is cold when the stove is cold so conditions are not favorable. I'm not trying to say you have downdraft, but I's be surprised to see any heated two-story house, in winter where opening the stove flue and opening the door doesn't result in detectable downdraft.

TE

Happened to me yesterday, opened the door and could feel the cool air on my hands as I loaded. Maybe the dryer was on, I've noticed it before didn't even bother to investigate. Once the super cedar started going a bit no problem.

Been burning wood for a long time and you can use a damper for any thing you want including a boat anchor, but the orginal use for a damper was for control of the fire.

Not sure why my chimney at 18 feet would be so much different and not down draft any, have never been able to make it back puff either and that is with two different chimneys in the same spot one block and one metal.

Speaking for myself raybonz described my situation exactly. I live pretty close to the water but on the downside of hills on the shoreline. Plenty of trees on those hills too. So when the wind comes off the water we have high winds overhead on the lee side.

I have about 25" of 6" stainless in a masonry chimney and it happens sometimes. Maybe I should try a different cap but usually not a big issue.

And you're probably historically correct in what you've now just said. But practicality intervenes and some of us use the damper in additionally useful ways. As you have just now seen, and may continue to see in as yet to be written posts.

We have come full circle, that is all I said in the first place, would not use one for controling a down draft because most of them have holes in them.