Fireplace problem

Perhaps there are obstructions in the chimney itself (e. g. wildlife - I know that's icky, but sometimes squirrels lose their footing and you can guess the rest). Has the chimney been inspected?

Oh, and welcome to Able2know!

Sometimes with these fireplaces (the kind that are popular in ski chalets) is they need a kick to get a draft going. When the fire is started have your friend start burning a roll of newspaper . then stick the burning roll up the flue a few inches. do this for a few minutes until you see the draft going, All of a sudden the smoke will stop lazing around the funnel and will quickly begin an upward draft.i These kind of fireplaces dont usually have a smoke shelf so the draft uses the entire room to get going. they usually are a design problem

Fireplace problem
There are no obstructions at all, a chimney sweep came out and cleaned it. After further research I think the wide open area of the fireplace (360 degrees) may simply be too large for the flue to draw no matter what is done. Some of it can be enclosed with masonry but in order to preserve the beauty of the circular design maybe the rest could be enclosed with tempered glass. Any thoughts?

You shouldn't have to enclose it. It sounds like the problem is with heat exchange. Too much cold air is sitting in the flue pipe. Did you try preheating the flue pipe like Farmerman suggested?

Also, how far does the chimney extend above the roofline of the house? In many cases extending the chimney height will greatly improve draw.

very good point fishin, our nrighbors had to do that with one of their flues that they had opened and returned to use as a fireplace. the contractor called that to their attention when , at first the fireplace had a lousy draw.

Fireplace problem
They had tried to burn paper right under the flue but they said that didn't help. It is starting to sound like the stack is too short. I'd have to see how far it extends above the roof but from what I understand you can't simply extend it with a galvanized flue without it being insulated. Is this correct?

Re: Fireplace problem


You'd have to check local building codes (the people that sell stove pipe should be able to tell you) but you'd normally use triple-wall pipe to continue the stack if that is what is already there.

You could put on 6 ft of uninsulated pipe to test though. If that fixes the problem then they could invest in the triple-wall (which is pretty expensive..)

OK, thanks, I appreciate all the suggestions. I think the next step is to test some of these ideas.

Well, we added the extension (about 7 ft.) and it did the trick, at least we thought. When we tested it it was relatively warm out and everything worked fine but when it got colder the draw was reduced significantly. I'm thinking this was due to the exposed flue extension being cooled too quickly by the cold air and losing the draw. Do you think this reasoning is sound? If so, what can we use to insulate the flue with? It is a double walled extension.
Jeff

Huh. So it worked for a while but not when the temps cooled more. *scratches head*

Try one more trick. Open a window in the house an inch or two (if the wind is blowing open a winoiw that faces into the wind). Then preheat the flue and light a fire. Once the fire has been burning for 30 minutes or so close the window and see what happens.

If that "cures" the problem then your friend needs to find a way to get outside air into the house at the fireplace. Older houses never had this sort of problems because.. well.. they weren't insulated so they were drafty as heck. Newer houses are built to a point where they are pretty much air tight.

The flue is drawing air from the house and sending it up the chimney. Your's may be drawing more air than the interior of the house can provide
so you end up with unequeal air pressure.

The window test just allows more outside air in to equalize things.

We've tried the window trick and it didn't do anything. The house is old and in a very rural area and is full of holes so pulling air from the outside is not the problem. I'm still leaning toward the galvinized double walled flue extension cooling down too much because of the exposure (7 ft.) I would like to insulate it somehow but obviously in a safe manner. Any suggestions ?