Burn Time for Old Penn Stove

Greetings to all,

as a first time coal stove user (and poster here) I've found this forum to be an invaluable source of information. Thanks to all who've taken the time to contribute your knowledge. There's an old Penn stove in my basement that I'd never used until this season. With fuel oil prices being what they were earlier this year I decided to educate myself and give it a go. Due in large part to this forum I've had pretty good success and managed to keep the stove going for seven days during a cool spell in October. Unfortunately I've been unable to find any info about this stove so I'm in the dark about what to actually expect from it.

I'm primarily interested to know if anyone can suggest how long I can expect the stove to burn once filled. It's a round stove with a small firebox. The firebrick is 13 inches in diameter and only 5 inches deep. It's seems pretty easy to control so I believe it's reasonably tight. I've been filling right to the top of the firebrick and mounding a bit higher towards the middle. Once I close down the air and damper the stove settles to a temp of ~400-500 with the stack at ~250. The longest I've been able to go and still be able to revive the fire was 7 hours with 6 being more typical. Given the small firebox that may as good as it gets with this guy but again I have little experience and zero info about this particular stove. Any thoughts would be greatly appreciated.

Regards,

Rick

Your 13" diameter is a small to medium size grate area but the 5" really kills you. The size gives you the btu's, the depth adds hrs of burn time. I'd guess the stove is about a 40,000btu unit and your six hr burn times sounds just about right. Post an image or two.

Thanks Cap - I suspected that was the case. Here's an image of the stove. She ain't pretty but she's functional.

I'm pretty sure those stoves have a round cast iron firebox. They are almost identical to a Chubby stove and should easily get a 12 hour burn. Check the gaskets on the doors and the damper. If there are firebricks inside I would remove them and check the cast iron firebox.

You can probably mound the coal higher than the firebrick, the hot part of the fire is not at the top, so there would be no harm from some fresh coal resting on the top of the firebrick against the cast iron.

I too think that you should be able to cool it down some and extend the burn if you can seal it up better.. use a smoke source, a cigar, cigarette, incense stick or even a candle flame and check around the doors and vents for air leaks..

The sliding type of air vent often isn't very tight against the door, if it has a tensioning bolt or spring, tighten it up to reduce the gap/clearance.. you may even want to remove the slider and sand/ polish the sliding surfaces to make them mate closer..

A 4-500* stove temp and 250* stack is still pretty hot, I think a stack temp of 150* is do-able if you can shut down the air some more.. if you have a really strong draft this may not be possible..

if you have a strong draft, I'd recommend a Barometric damper to control the draft,, this will pay for itself in lower coal use, and longer burn times..

Greg L

Greg is correct regarding the barometric damper. When I was younger my brother had one of these stoves in the shop. We put a barometric damper on and the burn time increased quite a bit. The the stove would hold well overnight and kept the shop nice and warm. Made a big differnce.

Thanks to all for your thoughts,

In my original post I was mainly concerned with how long this little guy might go when it was really humming along. Since then I've experimented with closing the air down considerably (you're absolutely correct Greg) and have been able to go for well over eight hours and still easily revive the fire. The stove isn't putting out a great deal of heat in that state but that's fine during the night. I usually work from home so during the day I can tend to it more often if necessary.

I was pleased to find that I had been starting to employ many of the suggestions you folks have made. I did replace the gaskets, checked the damper and generally made sure the stove was as tight as it was going to get before firing it up for the first time. The firebox is round and small (only 5 inches deep as mentioned previously) so I don't expect exceptionally long burn times from the stove. Choking the air down more and banking the coal higher than the firebrick towards the center certainly has helped in that respect though.

The chimney does draft very well even with outside temps in the 40- 50 degree range. Too much draft may become more of a problem as it gets colder. I'll have to keep an eye on that. There's also an oil burner venting into the same flu and I've adjusted it's baro slightly to help keep the coal stove's draft in check for now. That actually works pretty well though I'm aware it's not as effective as the stove having it's own.

I'm sure that I'm experiencing the same learning curve as anyone else does when getting started with coal. It's certainly different than wood and using an old, no frills stove probably doesn't make it any easier (or maybe it does). Along with this forum, a big factor in getting better results for me has simply been getting more familiar with the stove and more confident in the necessary techniques. Early on I wasn't shaking the stove down nearly as much as I needed to. I was also a little paranoid about choking the air too much for fear of killing the fire. Thanks to this forum for making the whole experience much easier.

Rick