Questions regarding Appalachian 36BW

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New Member
Dec 30, 2014

I am a new member of the forum, but I have lurked here for a while educating myself on cat and non-cat stoves, burning techniques, and all sorts of other interesting wood burning topics. This is a great forum with lots of info, but I haven't seen a whole lot about these particular units. I've had a ~1994 model Appalachian 36BW insert since 2000. It was previously owned by my uncle and likely not used very much while he had it. It still has the original cat in it which still lights off with ease and burns with no smoke. I originally thought it was time to replace it based on the data here which says 10 years is about the most I could expect to get out of one; however, this stove probably doesn't see the amount of use that one from up North might see. With that said, the house is maybe a little over 2400ft^2 two story w/ no basement and the chimney is a large brick with square liner, approx. 25' tall, and the 8" flue pipe from the insert goes maybe 15' up inside the liner.

I have noticed that it doesn't throw a ton of heat but it is easily capable of keeping the whole house an average of 74degF or higher if we run the downstairs air handler to help mix the air every few hours. We started using this insert exclusively for heat after receiving a $300+ electric bill one month last winter. We still have propane space heaters and the two central units with electric heat for backups. The house is well insulated and isn't hard to heat (in fact, the electric is probably overkill).

I have learned a few things lately as I have researched woodstoves. I believe this stove would run a little more efficiently if I were to install a block off plate above the insert. From what I've read here, a lot of heat is likely going up the chimney. There are occasions, where it doesn't seem like it throws the heat like the older units my grandparents had, but part of this is the nature of a cat stove from what I understand. I have to say, I have been impressed by how well it operates, but there are a few things that I have questions about.

1) This unit has an air wash system for the glass, but it doesn't take much to smoke it up and leave a good opaque layer of what I suppose is creosote on it. I see there are holes on the side for this and they are not plugged, but the system doesn't seem to be effective. I tried burning the unit harder for a while before taking air out to see if it would clean up but it doesn't. Anyone have experience with this issue on these stoves?

2) Probably related to #1 above, the stove always had a "rack" inside that looks like what you might put in a open fireplace to hold wood. It's made from square steel material, and looks to me like it may not be original to the stove. Nevertheless, we've always kept it in there (I never questioned it till now) and loaded the wood on it what I believe is called E/W orientation. The potential problem I see with this is not being able to fully load the stove, and the wood is never really close enough to the door to allow the heat to burn off any creosote. This is only a theory of mine, but I am hopeful that someone can offer their thoughts on proper loading and whether the rack belongs there or not.

3) I've always heard growing up that pine is not to be burned in a fireplace, woodstove, etc; however, it seems from reading on here that it is acceptable as long as it is dry and seasoned? If so, this is great news to me since I live in the pine belt and own a tree farm of planted pines. We have always burned hardwoods, mostly different varieties of oak.

4) The stove never had any kind of temperature instrumentation on it, but it sounds like it would be a good idea to have from what I have read on here. With that said, it hasn't been an issue in all the years we've operated this stove. In fact, it is pretty straightforward to run by "feel" if that makes any sense. Being an engineer and taking more interest in the stove, I feel compelled to add temperature monitoring to better optimize how I run it. Any recommendations for this type of unit for what I need to have?

5) One thing I've noticed is that this unit seems very difficult to overfire. Most of the time it seems like the cat is only working hard when air is cut back enough to the point where there is little to no flame in the firebox. More air just makes smoke/CO combustion occur inside the firebox so only a small amount is left for the cat to eat. I generally run it by getting a healthy fire with the door open and closing to door to continue burning-in and drying the wood. I then engage the cat when I feel like enough heat has made it into the cat area. I generally gauge this on how warm the top feels, the amount of radiant heat, the appearance of the wood being burned, elapsed time, and by watching for whisps of flame that disappear just before being sucked through the cat. Once the cat is engaged, I monitor the flame and look for slow, lazy flames that sort of float around in the firebox. Generally, I'll start cutting back on air over a period of time and watch to make sure the cat doesn't glow brightly or experience a lot of flame impingement. The cat doesn't always glow, but it can be a good indication of light-off if I do see it. I usually feel the top of the stove increase in temp sharply to know if the cat achieved light-off. Once it is cruising, I usually see just the occasional lazy flames and a dim glow in the cat. Interestingly, I recently placed a cup of that scented warmer wax on top and it seems to also be a good indication that the stove is working well once it starts to melt, and it tells me when it's almost time to reload if it starts to set up.

Sorry for such a long-winded first post, but I've had these things on my mind and haven't been able to get much farther with them from searching the forum. Please let me know what your thoughts are on any of these items.

Sorry your post sat so long before approval for posting - getting late.

The first thing everyone is going to want to know is how long your wood had been split and stacked, and if you have a moisture meter.

You would be way better off with a full, 8" liner all the way to the top. Cleaning would be much easier, as well. What is the current 15' pipe made of?

Block off plate can only be an improvement.

1) Dirty glass is pretty typical when it comes to many cat stoves. Again, draft and wood moisture can make a difference.

2) I don't know of any wood stove that has a grate in it, unless part of an ash removal system. Most manufacturers specifically advise against it, and often void warranty.

3) Yep, pine is as good as any other wood if it's dry.

4-5) seem kinda related. Thermometers are not necessary, but good for reference, and a big help in burning efficiently. I prefer a point and shoot type IR thermometer. Sounds like you are doing a pretty good job without one.
36BW is pretty close to my Bay 52.

1. Airwash sucks in these stoves, expect to clean the glass with a razor blade if you wish to see the fire.
2. Fireplace grates are not needed, you want a nice amount of ash for the wood to sit on
3. Seasoned pine burns fine
4. You should be able to add a Condar Catalytic probe above the door, you should see a screw next to the bypass handle, take that out and insert the probe there
5. Cat probe will help a lot to let you know when to close the air and bypass

If you are interested you can check out my thread on the 52 bay and it might help answer some other questions:
Thanks for the replies.

Jeff: Wood has been split and stacked for about 10-12 years, covered with tin. A lot was given to us years ago when my grandfather converted to gas heat. Some of it is a little newer, but no more recent than three years. This year (around July) we clear-cut some of our land to replant and we ended up with about another 6 cords (still got a ton to cut). This wood is mostly Oak with the rest being hardwoods of various types. It spent the late summer in 90+ degree heat and we cut and split much of it around September. I am trying to get back ahead again with this wood so my plan is to let it sit for at least a year or two before burning. As of this week, I have started throwing a split or two in every now and then but I make sure to let it "steam out" longer before engaging the cat. The flue pipe is stainless if I'm not mistaken. I'll try to get a Fluke IR thermometer soon. I've always wanted one anyway to use for other things I tinker with, and I think I have a connection to get one for a good price.

Mellow: I usually let the ash build up and stay about even or just below the bottom of the grate. The biggest problem I see with it is it does not allow me to load N/S and it limits me a lot on how full I can actually load the insert. I think removing it would also let me get wood closer to the glass which may help with burning off the deposits. Also, read about the screw by the bypass handle, but this stove does not have one. It may be on top, so I will have to take part of the surround off to check.

Any general recommendations on loading E/W vs N/S on this stove?

I load either way in mine, if I want a quick hot fire I load N/S, if I want a good long burning fire I load E/W.

Ditch the grate, the key is to do an air trench in the ash front to back down the center when loading E/W, I also mound up the coals in the back so the fire burns back to front and doesn't ignite all the wood at the same time, it just winds up overloading the cat.
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