Did I buy the wrong stove?

[SpaceBus]

Any updates on the VC? Changing to a different stove is not going to save any money, I agree with Ashful on that.

 

[Ashful]

So in hindsight, maybe a cat stove wasn't the best idea for me as I get the wood early spring and stack it and pray. It's burned the same year. I love my stove though.

The primary advantage of going to a cat stove is most often their ability to burn lower and slower than a non-cat. There are of course always exceptions to every rule, this one included, but in general… cats have longer burn times, associated with lower available burn rates.

So, did you go wrong, in buying a cat stove? Only partially, as your stove can still work fine at the medium burn rates where you’d have likely been running it’s non-cat competition. With wet wood, you won’t be able to take full advantage of the primary turn-down benefit, while accepting the small but non-zero cost of replacing a combustor every 10,000 - 15,000 hours. Not a huge deal, and perhaps you’ll be able to fix your wood supply issue, over time.

If wet wood was known to be part of the equation at the outset, most would have recommended the non-cat, as they may have better durability than shocking a ceramic combustor with steam on each reload, and knowing that trying to burn at the cat stoves lowest rates will only cause frustration. But the steam shock issue can be resolved by running a steel cat, and you will soon learn where the useable range of burn rates are for your stove with your wood.

What woodstoves do you have?

That answer has changed a few times in 10 years, but presently I’m on a pair of BK Ashford 30.1’s. I will likely stay with BK for any future wood stove (as long as they continue to have some big pretty model), I’m just thrilled with their performance, but I have toyed with the idea of replacing one of the wood stoves with pellet.

Any updates on the VC? Changing to a different stove is not going to save any money, I agree with Ashful on that.

Yes… given the latitude of the OP, I suppose that’s the case. But my post on ROI was actually arguing that stove purchases can often pay for themselves very quickly (eg. 2 years), in the northern half of our 48.

 

[bikeshopguy345]

Any updates on the VC? Changing to a different stove is not going to save any money, I agree with Ashful on that

Yes, post #53, #63, and #70 are the latest.

In summary, I believe adjusting the automatic damper chain a bit longer was exactly what the stove needed(and cleaning my chimney cap).

I plan on updating Friday when we get some cooler weather again.

Thanks again for everyone’s input. I think I am going to be very satisfied with the setup now.

 

[bikeshopguy345]

Nah… stuck with the Jotuls a few more years, after that squirrel forced a rebuild upon me. I think the Ashford upgrade happened around 2015.

In any case, bikeshopguy345 may still want some form of screen up there, to keep those curious squirrels out. Just something coarse enough to avoid any likelihood of clogging (think 5/8 - 3/4 inch mesh). A bird in your stove is a sad day, but a pissed-off and soot-soaked squirrel in the stove is the day you may need all new carpet, drapes, and furniture.

My homeowner's insurance requires a spark arrestor. Even if they didn't, I think I would leave it for critter protection.

 

[Ashful]

My homeowner's insurance requires a spark arrestor. Even if they didn't, I think I would leave it for critter protection.

Yep, the question is grid size. I did some research on this way back in 2012, and from my decade-old memory, I see to recall most insurance and/or state requirements call out 5/8" or 3/4", hence the numbers I posted. Unfortunately, some cap manufacturers choose to use 1/2" or smaller, it may be less expensive. The smaller grid size is more prone to the clogging you had experienced.

Do your own search on this, don't rely on my old memory, but I suspect an increase in size may be a benefit for you.

 

[bikeshopguy345]

Yep, the question is grid size. I did some research on this way back in 2012, and from my decade-old memory, I see to recall most insurance and/or state requirements call out 5/8" or 3/4", hence the numbers I posted. Unfortunately, some cap manufacturers choose to use 1/2" or smaller, it may be less expensive. The smaller grid size is more prone to the clogging you had experienced.

Do your own search on this, don't rely on my old memory, but I suspect an increase in size may be a benefit for you.

Good to know! I’ll measure it when I get up there again for spring cleaning. It is Duravent and from what I can tell online it is 1/2" mesh. My insurance just calls for a “UL listed spark arrestor." Modifying a UL listed product may render it no longer UL listed?

Either way, I just plan to keep an eye on it. I think it'll be fine now that I won't be using random junk from the recycle bin for fire starting.

 

[Ashful]

Good to know! I’ll measure it when I get up there again for spring cleaning. It is Duravent and from what I can tell online it is 1/2" mesh. My insurance just calls for a “UL listed spark arrestor." Modifying a UL listed product may render it no longer UL listed?

Either way, I just plan to keep an eye on it. I think it'll be fine now that I won't be using random junk from the recycle bin for fire starting.

Yes, I do believe modifying it would invalidate the UL listing. In that case, if it continues to cause you problems, you may have to shop for another UL listed unit with a larger size mesh. No sense in messing around with your insurance.

 

[wjohn]

I haven't had near the buildup issues you've had at the cap, but here's what my Metal-Fab cap looks like. The openings look bigger, but there's also more surface area for stuff to stick to since it's stamped out of a flat sheet of metal vs. the hardware cloth looking deal on yours. I think you'll be okay with some burning habit changes like you've mentioned. I can only imagine what your cap would've looked like with the BK you were originally considering

 

[bikeshopguy345]

Wow, what a difference 1 link in the chain makes!

My wife did a top down cold start on a full load of medium sized white oak splits last night at 830PM. When I got home at 11:30PM the firebox still appeared mostly full, and was cruising around 450F with nice slow rolling blue secondaries. The damper flap was fully closed. I am assuming it is closing around 350F, but I still haven't been able to witness it. At 11:30PM I threw in one medium sized split to top it off. As it off gassed, the stove peaked up to about 600F briefly, then settled down to cruise just below 500F. At 630AM the stove had a really good amount of glowing coals in the back! The stove temp was around 250F. Some of the coals still resembled a firewood split. We raked the coals to the front, added some splits, and it was up and going in no time.

This is such a huge improvement. Previously we were struggling to find any coals at 6 hours and the stove was getting too hot in my opinion. I never felt like I could really pack it without being nervous about it running away. Now that the air control is actually closing the damper, it is like a completely different stove. Instead of burning hot and fast, it seems to just want to cruise on and on at a medium burn rate. I think 10 hour reloads are not out of the question.

To top it off, last night's low was 27F and our heat pump was set to 68F. It never turned on. 100% satisfaction achieved.

Thanks @wjohn for all of the Aspen C3 specific information. Thanks to everyone else for helping me through this process.

 

[stoveliker]

Glad to see another user of a good stove on their way to happy burning!

 

[begreen]

Last night's fire was an exercise in frustration, but fortunately things ended well. At about the 1hr/300F mark the fire kept stalling out. The damper was almost closed at 300F so I though my new adjustment was starving the fire for air. I decided to remove the foil tape from the flapper to give it more air. I do no recommend using foil tape! I ended up using a pencil to just poke a hole in it. I think a small magnet would be much easier to deal with for covering holes on the damper.

Removing the foil tape did nothing. I decided to prop the damper fully open with butter knife. I still couldn't get the fire to go! This has never happened. I sat on the couch feeling frustrated, confused, and wondering what I had done to mess up my stove. It was then that I realized that I must have some kind of obstruction because I kept getting smoke spillage when opening the door, which has never been a problem before.

Fortunately last night the moon was bright. One trip to the roof at 11pm confirmed my suspicions of a clogged spark arrestor cap. I popped it off and by the time I was back inside the fire was already going. Things seemed to burn well and eventually stabilized around 500F. At midnight threw one medium split in and it peaked at 750F and I went to bed. The stove temp was just below 200F and there was a small pile of hot coals in the back at 9AM! I'm counting this as a victory! I think the damper is closing between 300F and 400F but I'm not entirely sure yet.

I am still looking forward to doing a cold start to coals burn time test, but will have to wait a couple of days for cooler weather again.

When we first started using the stove we used a bunch of junk from the recycle bin to start fires. Cardboard, glossy mailers etc. I think I must have disturbed enough ash in the system yesterday finish plugging it up. Still crazy how it went from seemingly over drafting to clogged so fast.

Now to go clean this mess. Any suggestions?
View attachment 292192

That's a fine mesh cap for a wood stove. I think I would replace that screen with one with larger holes. It looks like 1/4" or 3/8" mesh. Remove that screen and go up to a 1/2" or 3/4" mesh.

 

[wjohn]

Nice work! Glad my experiences could help some. There did not seem to be a ton of information online about this stove when I bought it so I have been trying to document what I can for other current/future owners. Thank you for getting pictures of the chain/damper/bimetallic coil setup while you were in there. It sounds like you are in good shape now with the heat pump not kicking on for a night like that, in your climate.