Which stove pipe type to buy? Single wall, single wall, or single wall?

[wmarazita]

Hello everyone,

I have purchased the Englander 30NC from Home Depot (at this forum's suggestion) and had it delivered. It sits in my garage currently, and I will soon be moving it into position to replace the old stove (see photo). I have purchased side heat shields and it came with the rear heat shield installed. I will end up having a 8-9" clearance in the back of the stove and my "CTC" table states I can use a single wall stove pipe, which is what I would prefer to use (rather than double walled).

So my next set of questions are related to stove pipe!

I started looking at single walled stove pipe at the box stores (generally 24 gauge), and also on the Internet at various retailers (22 gauge). Wow, there are a lot of different options! Based on my installation, I believe I need the following pieces:

(1x) 6" x 16" (approx) straight piece crimped at stove end that will come out of the stove
(2x) 6" adjustable 90 degree pieces connected to the straight piece
(1x) 6" to 8" increaser (that is crimped on both ends) to connect to the thimble

Questions/suggestions:

1. Suggestions on brand of single walled stove pipe?
2. Best place to purchase product?
3. I am seeing conflicting info on whether I need to seal the stove pipe joints. To seal or not to seal? If so, what type of sealant and where to buy?
4. I have a crimper and sheet metal cutter. Can the 22 gauge stove pipe be easily crimped and cut?
5. How do I attach the crimped end of the 8" increaser to the thimble in the wall? I don't see how I can screw it. Can it just be shoved in and expected to be safe, secure, and not leak?
6. Any other questions, comments, or concerns that I am not thinking of?

My wood burning stove expertise consists of 14 posts (make that 15) to this forum and a lot of reading (on this forum), but I am excellent at following instructions and looking forward to installing this myself.

Thanks for all of the help so far and in advance for future help!

Bill

 

[DAKSY]

Based on my installation, I believe I need the following pieces:

(1x) 6" x 16" (approx) straight piece crimped at stove end that will come out of the stove

If you get a 24" piece of 6" x 22ga Heat Fab single wall connector,
you can cut it to whatever length you need & there will be no crimping involved.
The end you cut from will slide into your stove's flue collar...

(2x) 6" adjustable 90 degree pieces connected to the straight piece

Why adjustable & why two? Get a solid 22ga Heat Fab 90 deg elbow,& if you
do the math correctly, you should be able to run from the elbow into the chimney...

(1x) 6" to 8" increaser (that is crimped on both ends) to connect to the thimble

You can get by WITHOUT an increaser.
Run a straight section of 22ga Heat Fab into the chimney.
Run it AT LEAST one inch into the vertical flue so that
if you get any build up it'll run into the chimney rather
than down the outside wall.
Then you can insulate between the OD of the 6" & ID of the *" with rock wool.
Add a 6" trim collar & you're good to go.

Questions/suggestions:

1. Suggestions on brand of single walled stove pipe?

Any 22ga connector will work. Heat Fab is the one I'm most familiar with...

2. Best place to purchase product?

I would suggest a hearth shop. They specialize in what you want to do.
Big box & home improvement stores are pretty much worthless. IMHO...
A reputable hearth shop will lead you in the right direction. You are literally
playing with fire & if you make a mistake, death can result.

3. I am seeing conflicting info on whether I need to seal the stove pipe joints. To seal or not to seal? If so, what type of sealant and where to buy?

If you use good connector, three screws at each joint are all that is required...

4. I have a crimper and sheet metal cutter. Can the 22 gauge stove pipe be easily crimped and cut?

You do not need ato crimp - IF you cut the right end of the 22ga...

5. How do I attach the crimped end of the 8" increaser to the thimble in the wall? I don't see how I can screw it. Can it just be shoved in and expected to be safe, secure, and not leak?

Already addressed- above

6. Any other questions, comments, or concerns that I am not thinking of?

I would have the existing chiney cleaned & inspected by a reputable sweep.
You want to be sure it's safe enough to use

My wood burning stove expertise consists of 14 posts (make that 15) to this forum and a lot of reading (on this forum), but I am excellent at following instructions and looking forward to installing this myself.

Thanks for all of the help so far and in advance for future help!

Bill[/quote]

Good luck with your project!

 

[wmarazita]

Bob, thank you for the very complete and informative reply!

A couple questions:

I was thinking I needed two, adjustable 90 degree elbows because my flue collar is offset from the thimble by about 4 inches. That is to say, the hole in the thimble is not centered on the back wall. So, I didn't see any way to come straight up and make the turn with one 90 degree elbow. Is there another way to do this with just one 90 degree, fixed elbow?

What is "rock wool" and where would I get it?

FYI, the existing chimney was recently swept and inspected and all is good.

Thanks again!
Bill

 

[DAKSY]

Bob, thank you for the very complete and informative reply!

A couple questions:

I was thinking I needed two, adjustable 90 degree elbows because my flue collar is offset from the thimble by about 4 inches. That is to say, the hole in the thimble is not centered on the back wall. So, I didn't see any way to come straight up and make the turn with one 90 degree elbow. Is there another way to do this with just one 90 degree, fixed elbow?

I would lay out the center of the back wall & see if you can get a 6" piece of connector into the thimble without
any offset. You're gonna get an inch, maybe more of leeway, depending on the wall thimble ID.
It may mean that your connector is in contact with one side, but if the structure is built correctly,
that shouldn't be an issue.

What is "rock wool" and where would I get it?

It's similar to fibreglass insulation, but approved for hi-heat conditions...
Again, check a reputable hearth shop. One brand name is KAOWOOL...
I have actually used unfaced fibreglass & had the local JHA inspect MANY
installs & approve them, but you'll get a LOT of negative comments here if
you do it my way...

FYI, the existing chimney was recently swept and inspected and all is good.

You should be good to go!

Thanks again!
Bill

 

[wmarazita]

Thanks Bob! That all makes sense to me.

I was thinking that maybe two 45 degree elbows might work, if the offset is too great to go straight in (as you suggested). I drew up a model on Google Sketchup. From the picture, do you think this would be a good way to go? I don't know how much distance that the two elbows would shift over the horizontal stove pipe....it might end up being too far the other way!

I was looking at the Heat Fab elbows and noticed that they are corrugated. Does the corrugation on the inside make these elbows more difficult to clean?

Thanks again!!

Getting ready for the install and the shirt!

Bill

 

[Danno77]

Why would it be recommended to slap Roxul around the 6" pipe at the thimble instead of an increaser? Seems like the increaser would be cleaner looking and if you do get some turbulence where the pipe enters the flue (and you will, I imagine) you'll get some creosote buildup on the Roxul instead of on some metal pipe.

Disclaimer: I'm just theorizing here, I have no real life experience with this kind of thing.

 

[begreen]

Also, the 45's should pitch upward toward the flue thimble connection rather than being perfectly level. This will assist draft.

 

[wmarazita]

If I decide to use the increaser pipe at the thimble, Hoe does the increaser attach to the thimble? It doesn't appear as though I can screw it onto the thimble. Does it just stick into the thimble without any positive attachment?

Thanks