Can a stove draft TOO well?

[HawkinsHollow]

I just reinstalled our Englander 17-VL, just in time for the cold snap to get here. 9' of Duravent DVL double wall inside and 4 feet of Duravent Class A chimney leaving the vaulted ceiling living space. I fear the stove might draft too well with the new double wall flue pipes, is that possible? Even with the damper choked all the way down on lowest setting the stove is getting too hot. I think it is partially due to fuel load. Yesterday I burned all day and was able to keep it under control, nice slow burn with the secondaries just slightly kicking off. But I think that it might be because I did not stuff it full of wood. Last night when I packed it full for the night it took off like a freight train. Even choked down on the lowest setting it was on the verge of overfiring.

I put a new door gasket on it and it has a really nice tight feel when the door is closed so I don't think it is that. Anything else I should look at? After the stove cools off I am going to poke around under where the damper does it's thing to make sure it is sliding back and forth like it should. I know the damper is doing something because there is a noticeable difference between wide open and "closed down". Also might order a damper for the pipe leaving the stove as well. It is not a very nice feeling having a stove that you can't slow down if you wanted to.

 

[ponytug]

I guess it is possible to draw too well, but unless your damper is too small for your pipe, to me it is more of an inlet air/fueling item. If loading the stove up gives you issues, I would see whether you can restrict the primary air inlet(s) more, but leaving enough secondary air that you are getting good combustion, plus, of course, putting less fuel in, or in larger pieces.

FWIW: For overnight burns, I try to use larger diameter chunks to get slower burning, and less of a loading flare, although I do think every stove and installation has its own foibles.

All the best,

Peter

 

[mrmikey]

I know when I installed my stove quite a few years ago I couldn't figure out why it looked like it was burning too much with the draft on the stove completely closed. The heat it put out would drive you out. Problem was it was supposed to be completely closed and couldn't be as there was a drilled 3/8" hole that was intentionally designed to be open when it was to the full closed position. I guess the reasoning was that you couldn't smolder the fire? Fixed that problem by making a new slide without the hole, now when I close the damper it all but kills the fire.

 

[Snobdds]

The new EPA stoves do not shut down all the way to keep from having a smoldering fire. They want air flow to keep the exhaust clean.

I know on my stove at the cabin, I had to cut out a stop on the draft control to allow the draft slider to close tighter. It was keeping it a good 1/3 of the way always open.

You're going to have to trace your draft slider and see if there is a stop. If there is, take it out.

 

[HawkinsHollow]

I guess it is possible to draw too well, but unless your damper is too small for your pipe, to me it is more of an inlet air/fueling item. If loading the stove up gives you issues, I would see whether you can restrict the primary air inlet(s) more, but leaving enough secondary air that you are getting good combustion, plus, of course, putting less fuel in, or in larger pieces.

FWIW: For overnight burns, I try to use larger diameter chunks to get slower burning, and less of a loading flare, although I do think every stove and installation has its own foibles.

All the best,

Peter

I definitely try to do larger pieces of overnight burns, last nights had a few medium pieces in there. I can tell it is getting too much air when on it's lowest setting though. I tend to think it is an inlet air issue as well. After tonight it is supposed to warm up again so I am going to take the damper apparatus apart and see if something happened to it. Tonight as an experiment I am going to put a blast gate like you would have in a dust collection system on the inlet and see if I can restrict the airflow coming into the stove with that and see if it makes a difference. I also just bought an inline flue damper to add to the system.

 

[SPYDERLK]

I know when I installed my stove quite a few years ago I couldn't figure out why it looked like it was burning too much with the draft on the stove completely closed. The heat it put out would drive you out. Problem was it was supposed to be completely closed and couldn't be as there was a drilled 3/8" hole that was intentionally designed to be open when it was to the full closed position. I guess the reasoning was that you couldn't smolder the fire? Fixed that problem by making a new slide without the hole, now when I close the damper it all but kills the fire.

Careful. As the stove smoulder cools the slide will try to open but the thermostat coil may be unable to apply enuf force against vacuum. .. Then finally it jerks open a bit. That smoulder smoke is mildly explosive.

 

[HawkinsHollow]

The are 2 main differences about the new setup that could cause these changes. I installed an OAK (outside air) and I installed double wall flue pipe. THe OAK is not plumbed into the stove yet, but it is loosely covered and only 8 inches from the stoves intake. But it is not like my house was ultra tight before the addition, it was built in 55. BUT the new air being introduced right at the inlet could play a role.

 

[HawkinsHollow]

Careful. As the stove smoulder cools the slide will try to open but the thermostat coil may be unable to apply enuf force against vacuum. .. Then finally it jerks open a bit. That smoulder smoke is mildly explosive.

There is no thermostat coil on this stove. All manual.

 

[jk96]

Do you have both a flu damper and air intake damper on that unit? Are you choking both down if so? Our unit uses a 14 inch ID flu. It drafts almost instantly with any heat. Even with a a 44-in fire box we have no issues controlling how hot it gets when using a combination of both air intake and flu dampers. If it only has an air intake damper, no flu damper it sounds like the unit is not restricting air flow enough

 

[HawkinsHollow]

Do you have both a flu damper and air intake damper on that unit? Are you choking both down if so? Our unit uses a 14 inch ID flu. It drafts almost instantly with any heat. Even with a a 44-in fire box we have no issues controlling how hot it gets when using a combination of both air intake and flu dampers. If it only has an air intake damper, no flu damper it sounds like the unit is not restricting air flow enough

It does not yet have an inline flue damper. I just ordered one to install.

I think you are correct, I think the inlet air damper is not restrictive enough. But in the
previous install I never had a problem closing the inlet damper and choking the fire way down. Not sure what changed, but I will figure it out AND install the flue damper and be good to go I hope.

The other thing I noticed is it burnt that load up WAY too fast. I have a nice ash round and 2 large chunks of cherry and they were GONE in about 2 hours. That is unacceptable! I mean this stove has never been an all night burner but still, 2 hours is pitiful! Need better air control to get longer overnight burns.