Info/Advice/Comments on Carolina (Bat Cave) Challenge II (III?) Installation

[Slocketman]

Recently acquired my first wood stove (catalytic insert really) & I've learned quite a bit already from the googles & forums here but could use some advice / anyone's comments on this insert, having it installed, & using it to heat my ~1700 sq ft. 2-story home. I'm excited to get it set up and have that first burn but want to make sure I get the best parts for the money & have it done right!
I've used my parent's insert & woodstove before, both of the older style with blower fans, but haven't seriously looked at it all until now.

It's a Carolina Challenge II insert/stove freshly refurbished from someone who does this often & it looks to be in good shape:
- welds in the firebox and all around look solid
- nothing seems warped
- 3 speed fan runs nice & quiet on all positions (unsure if the auto setting works)
- new firebrick
- new door gaskets
- ceramic catalytic combustor looks to be in good shape

I understand the company used to be Bat Cave and is now High Valley. I'm curious if it's somehow a Challenge III model as the specifications plate has the "Challenge II" part scratched out and a very clear "III" scratched into it. (picture attached)
(the expired eBay listing has more info, I can take the link down if it's not kosher)

8" Chimney Liner
I've had 3 quotes to install an 8" insulated stainless steel liner and have been researching brands/alloys/types to figure out what I want to go with. Currently looking towards single-wall heavy flex 316Ti liner, though honestly I get the feeling even the budget 0.005" 316Ti liners would be fine with 1/2" insulation wrap if I'm careful to sweep with non-metallic brushes. It seems they all have "lifetime warranty", but that probably doesn't include paying anyone to have it removed & reinstalled, so I'd like a nice durable liner that'll hopefully last a decade+ with moderate use (likely won't heat the whole house with wood full time every winter).

The heavy flex (0.010"-ish) 316L liners look to be the current winners on price vs. quality for wood & maybe a bit of coal burning but I'd like everyone's suggestions on what liner to go with.
After finding some comments here on them I've ruled out the "smooth wall" two-ply type liners for fear of delamination during installation, but I haven't seen any pros/cons to the double wall pre-insulated liners (though I'm not sure that type would fit in my chimney with the extra thickness/inflexibility).

(* Side note: the local companies I found need to actually include what brand/type of liners they're installing on their quotes, none of them did and when I called later one said: "No one's ever actually asked us for details on the liner". Wow. They would've used a 0.005" 304 alloy liner if I hadn't mentioned this insert is also rated for coal.)

Installation Notes
- Current gas line, logs, & glass doors will be removed. They're not the good kind that radiate heat anyway.
- 25' mostly exterior (bottom half is in attached garage) brick chimney w/ clay flue tiles will first be swept & inspected
- Double lintel doesn't leave much vertical space
- Decision between pushing insert back further into fireplace & re-mounting surround further forward than OEM or using some sort of sliding adapter hat to join the insert's exhaust to the flex liner (leaning towards pushing insert back, better draught with a direct mounting)
- Current rectangular flue damper & some bricks will be cut out to allow the 8" flex liner to fit
- Liner would be wrapped in 1/2" insulation & then a stainless steel mesh
- There's a decent offset to the flue that the liner might not be able to bend past, so an adapter would be used
- I think the quotes currently would just use mineral/rockwool insulation stuffed around the liner in the first section of flue to seal it in. Would it be better to have a metal plate fully sealed to the brick & liner there?

More Questions/Thoughts!
- Do the surround plates need to be installed, or would it radiate heat better without them (since it's meant to be installed both as an insert or freestanding stove)? Would it still be to code? What if heat shields were attached to the edges of the brick to ensure the wooden mantle surround doesn't heat up?
- It'd be really nice if not using the surround plates would give me enough space fit a cooking pot/pan on that top edge. I also like the look of it sitting back among all the brick better than the flush look with the metal surround plates blocking the opening.

- Should a key damper be installed in the flue? It has a single air inlet adjustment on each side of the door and a pushrod to engage the catalyst but no other adjustments.

- Suggestions on catalytic combustor thermometers / mounting ideas
- Is the Condor Watchman electronic thermometer any good? I'd need one with a longer probe than the typical ones come with (maybe 2' or so?) to reach the combustor which is directly below the flue opening.

Mad Scientist Mods:
- There's nothing to block flame from directly hitting the catalytic combustor, could a DIY flame impingement plate be welded in?
- Should I add another strip of gasket vertically along the edge of the right door? That section where the doors come together would just be metal on metal currently (not airtight?).
- Should I add gasket to the ashpan? The ash cleanout door is fairly tight but air could be pulled up from there past the unsealed ashpan.
- Should I add a course of firebricks along the inner wall of the firebox? There's just a layer on the bottom currently. No tabs or other securing mechanism for bricks to be ran along the sides.
- Any other ideas on modifications for safety/efficiency?


</end wall 'o text>
Finally pictures! Everyone likes pictures ( ͡° ͜ʖ ͡°)

 

[Slocketman]

Random thought:

I'm probably not going to even try to burn much coal, but I wonder if closing the air inlets & opening the ash pan as a sort of secondary air inlet, combined with adding some sort of coal burning grate on top of the open ash cleanout plate, would allow for the bottom-up airstream coal usually requires to burn well.

Still wouldn't have any type of grate shaker but it might make for a good experiment once I've got everything else figured out.

 

[Slocketman]

Would anyone happen to have a scan of, or know where I can find, a manual for this insert?

 

[Slocketman]

Currently trying to decide between the 0.006" thin 316Ti alloy flex liners (Rockford), the thicker 0.010" 316 alloy heavy flex type (Lindeman: Premier Flex Lite), or the pre-insulated double wall 316Ti (Chimney Sweep Online: Forever Flex).

Ideas?

 

[begreen]

Took a look at the eBay ad. $2400 is a very stiff price for a 1982 stove, even fully restored. The seller's claim that it will heat better than a modern stove is bunk as is the claim that a new insert will cost $4500 or more. A new High Valley 2500 insert is still made with 1/4" steel, seals tighter, burns cleaner and is ~$3000. ($2600 with Stohl discount)

Is the current setup a masonry or a prefab zero-clearance fireplace?

Key dampers don't go on inserts. The liner is not made for them. It's ok to run the insert without a surround if there is a full stainless liner installed.

 

[Slocketman]

Thanks for the info. I must admit I made the purchase too hastily as I was taken with the aesthetics of the double doors, huge rectangular glass, & general style compared to the newer stoves. Not sure I'd do it again now that I've researched stove efficiency more.

That said, this Carolina is probably overkill for my 1700 sq. ft. R60 insulated home, so if it was super efficient it might end up being too hot (though I could've gone with a smaller new insert, oh well). I'm in climate zone 6a and will be using wood to supplement gas heat (or replace it entirely if I get enough wood & keep up with making daily fires),

The fireplace/chimney is standard mid-70's brick/cinderblock, has a square flue with clay tiles, and a double lintel that the installers say makes this a bit more difficult. Originally designed for open wood burning but had gas logs and glass doors added at some point.

Damper: great, one less part to buy.

Surround: Glad that's not required with the liner. I was checking out someone else's thread on running with no surround & insulating the brick surrounding the stove with roxul & cement board to reflect heat back into the room; it seemed to increase the efficiency/heat output measurably.
My chimney is mostly exterior, so it wouldn't help heat the house to have the bricks soak up heat.

 

[coaly]

Damper: great, one less part to buy.

Isn't the spring handle a built in damper pull rod at top above doors?

Did the manufacturer have any old paperwork from their old model line?

 

[Slocketman]

@coaly : That middle spring handle is indeed a damper pull rod, but it moves the plate with the catalytic combuster.
So when it's fully pushed in the combuster is fully engaged. I was wondering if I shouldn't also have some sort of damper to control exhaust airflow while the combuster stays fully engaged.

If there is paperwork I haven't been able to find any yet. The High Valley website specifically says they don't have any of the old Carolina / Bat Cave manuals, but I'm sure they're floating out in the aether somewhere.

 

[coaly]

The flue damper isn't for the stove, it controls the chimney. It would only be required when you have too much draft. It is a variable resistance in the pipe that slows the velocity of the rising gasses. The combustor in your case is the resistance. A probe thermometer above CAT will show when you have ignition. The flue size is what is important and should be the same size as appliance outlet in diameter. (I'm sure that will be one of the requirements you find in the manual)
I use Search Tempest to search Craigslist nationwide for key words. As you find these for sale, eventually you may find someone with a manual. That's where most all of the Fisher manuals came from in the Fisher section. It takes years, but they do surface eventually. I had the seller of an Insert send me their manual from California, scanned it and sent it back to get that one uploaded. Later one came up for sale on eBay so I could add it to my collection of originals.
I finally found the note on their website under PARTS where they state no parts or manuals are available for the older stoves. You would think under the FAQ's they would give support for the older models since the Stolls bought the original company that made them. Even if the Buchanans took the paper work with them, I'd find paperwork from old customers. If it's copyrighted, there is no law preventing it from being distributed freely such as I do with Fisher manuals. If you find one, feel free to scan and send to a mod or webmaster to upload into the Wiki section for your stove. I notice the manufacturer links Hearth.com on their webpage for information, so a link to their old manuals would probably be added as more info becomes available.

 

[coaly]

Random thought:

I'm probably not going to even try to burn much coal, but I wonder if closing the air inlets & opening the ash pan as a sort of secondary air inlet, combined with adding some sort of coal burning grate on top of the open ash cleanout plate, would allow for the bottom-up airstream coal usually requires to burn well.

Still wouldn't have any type of grate shaker but it might make for a good experiment once I've got everything else figured out.

The square inch area of the ash clean out is too small for the firebox size. The ash drawer would need gasket material to seal and prevent running wild. Opening ash pan door is far too much air and will result in flames to the top of insert. Burning coal with ash pan door open can melt grates and damages stoves very quickly. The grate or basket needs to be elevated at least 2 inches and no air can leak around basket. Air takes the path of least resistance and needs to be forced through coal. Secondary air when referred to coal burning is air supplied above fire for oxygen to mix with very flammable coal gas. Primary air comes from the bottom. It requires very very little secondary air and too much air flow rushes up chimney cooling it, losing draft, preventing the flow through coal bed. You only have 100 to 150* stack temp with coal and it requires a barometric damper to control draft precisely. Opening the ash pan door to get it going does not allow ignition of coal gas above fire. It is far too much flow and the gasses are lifted high above the firebed and out the stack without igniting. Closing air to the required setting allows the gasses to ignite properly BEFORE the firebed is too hot creating too much gas. When the coal bed is too hot and excessive gas is produced (gas is expelled from green or fresh coal) it can light violently with explosive force out the stack and back out the intake. You need experience with a properly working coal burner before experimenting with coal.
The CAT is also open during coal burning for maximum flow.

 

[Slocketman]

Thanks for all the info.
Sounds like I'm better off not bothering with any coal in this stove.
I was planning on installing a probe thermometer right above the cat, currently looking at the Condar Watchman electronic though I'm not sure which ones are best for the cost.

Hopefully I run across someone else selling an old Bat Cave / Carolina with a manual so I can upload one here.

 

[coaly]

Here's the manual for the 1500 and 2500 High Valley Catalytic if you haven't found one. Can't imagine your operation is much different.

 

[Slocketman]

Thanks, it looks like operation of the catalyst damper is similar, even though I don't have the 'under fire' air control like the High Valley 2500.
I imagine the High Valley's have some sort of plate under the catalyst to prevent flames from directly reaching it, the Carolina design allows direct flame under the catalyst (which could erode it prematurely from what I've looked up about catalyst maintenance?).

It's getting exciting! Parts have been delivered from Rockford & Lindemann's, I went with the National Chimney Premier heavy wall (0.010") flex liner in 316 alloy hoping that would hold up better than the 0.005" 316Ti types. Also got the 1/2" foil-faced insulation kit with the stainless mesh wrap as my chimney isn't fully inside the house.

Installation is scheduled for next Thursday (3rd), any advice on the little details I should pay attention to when it's all coming together?
A metal flue block-off plate won't be installed then (they'll likely just stuff insulation around the liner), but I plan to fab one up after it's in place & install that myself.

 

[coaly]

Did the WOW man (Joe) tell you what paint he used on it?

 

[Slocketman]

Heh, he is quite enthusiastic in that eBay ad; a bit too much color & caps for my taste. I had actually found a much more bland description on Craigslist first before I noticed the same stove listed on eBay as well when trying to research the make/model.

I didn't think to ask what type of paint. Hope it's the good stuff, I'll see how long it lasts I suppose. Will make sure to leave some windows cracked for the first few fires until it cures so I'm not inhaling the fumes.

 

[Slocketman]

Liner's here! A bit dinged up by FedEx freight but this end will get cut off anyway.




(edit: photo moderated to thumbnail size? I suppose I'll post them smaller in the future)

 

[Slocketman]

Has been installed & burning for a few weeks now, great success!
Pictures/details to follow.

 

[Slocketman]

Shiny! & very stinky! (just @ first)
But she's all burnt in now & will cook that room to 81°F when burning hard for several hours while the rest of the house runs around 75-78°F.

The surround plates are temporarily set up (the tea cup is structural...) but will be affixed to the brick sticking out about as they are now as heat shields to protect the wooden mantle.

One of the cinder blocks that makes up the back of the chimney had to be removed to allow access to attach the liner to the stove due to the very tight clearances. It was set back in place temporarily with caulk so I can make an access door there later.
The back of the chimney is in the garage, so if I make up a removable fan for the access door I could actually heat the garage with it when desired by pulling air from that area right above the stove. That would also help even out the temperature of the parlour compared to the rest of the house.



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