Englander 28-3500 - liner and stove pipe connection tips

[gandalf]

We just purchased a 10-year-old Englander 28-3500. It was used about 4.5 seasons according to the seller. Aside from some broken firebrick and missing rivet pins for the ash tray door (replaced by hack-sawing a pair of 5", 3/8" dia. crown bolts from Home Depot), the stove appears to be in good condition.
I'm preparing to re-line an unused clay (terra cotta) flue by dropping a flexible stainless (316Ti) liner inside the existing liner (7-1/16" x 11-5/8", inside dimensions). The clay liner extends above the chimney crown several inches. The liner + T connector and snout will be a bit shy of 30 ft. The flue is in a dual-flue chimney on exterior wall. One is currently unused and goes to a first-floor fireplace. The flue to be re-lined goes to the basement. Below the throat (? -- bottom-most clay liner section) is brick and cinder block construction. The throat area and stove pipe hole through cinder block into this throat area are offset somewhat. There is an interior cleanout door cut into the cinder block, below the stove pipe hole. An old oil boiler (since removed) had connected to this flue. There was a simple stove pipe that connected to the boiler and went through the stove pipe hole in the cinder block. There was no thimble and the pipe didn't continue upwards into the clay liner. From discussion with a local wood stove / stainless liner retailer, insulating the stainless liner isn't necessary. I am planning to use double-wall black stovepipe between the stove and wall (thimble?), with a damper somewhere in that run. The goal is something that looks similar to this (from another Hearth forum topic):



Can I safely connect the double-wall black stove pipe "directly" to a T-connector snout extending through the stove pipe hole in the cinder block, or do I need to have some type of thimble connector? If so, I'll possibly need to enlarge the stove pipe hole in the cinder block...?
Any ideas on insulating the stainless liner vs installing without insulation?
Other suggestions?

Thank you!

 

[gandalf]

Instead of bringing a stainless tee snout through the block wall, I think I'll have Selkirk's DSP6MA (masonry adapter; http://bit.ly/2kMBAw2) run through the block wall and connect into the stainless liner tee (or tee snout?) I'm not sure how exactly the masonry adapter is designed to connect to a tee connector/snout. If it needs to connect to a snout, I'll probably need to reduce the snout length. Any suggestions/concerns/tips?

Thank you!

 

[bholler]

From discussion with a local wood stove / stainless liner retailer, insulating the stainless liner isn't necessary.

How exactly did they come to that conclusion? Did they do a full inspection to confirm proper clearances?

As far as connecting the double wall whoever makes the double wall you are using should have instructions telling you how to do it with their components. Most will have an adapter for that purpose

 

[bholler]

Instead of bringing a stainless tee snout through the block wall, I think I'll have Selkirk's DSP6MA (masonry adapter; http://bit.ly/2kMBAw2) run through the block wall and connect into the stainless liner tee (or tee snout?) I'm not sure how exactly the masonry adapter is designed to connect to a tee connector/snout. If it needs to connect to a snout, I'll probably need to reduce the snout length. Any suggestions/concerns/tips?

That is not the correct adapter that is meant to co into a masonry chimney without a stainless liner

 

[gandalf]

That is not the correct adapter that is meant to co into a masonry chimney without a stainless liner

Are you sure? The installation manual (see figure D and section Installation Type #4) seems to suggest the chimney could be re-lined. Instructions in that section include, "Slide the Masonry Adapter into the opening in the chimney and into the branch of the Liner Tee." But maybe I misunderstood the instructions...

How exactly did they come to that conclusion? Did they do a full inspection to confirm proper clearances?

They came to that conclusion through my conversation with them. The stainless liner will run through/by masonry (clay tile, brick, concrete block) its entire length. It won't pass through/by combustible material.

 

[bholler]

Are you sure? The installation manual (see figure D and section Installation Type #4) seems to suggest the chimney could be re-lined. Instructions in that section include, "Slide the Masonry Adapter into the opening in the chimney and into the branch of the Liner Tee." But maybe I misunderstood the instructions...

Ok you are right the problem is that the way they tell you to do it the adapter and the tee snout are not attached at all which I would never be ok with. But you are absolutly correct that is how they tell you to do it.

They came to that conclusion through my conversation with them. The stainless liner will run through/by masonry (clay tile, brick, concrete block) its entire length. It won't pass through/by combustible material.

Yes I understand it will be in your chimney but does that chimney have the required clearance to combustibles? You say it is an exterior chimney so you would need 1" clearance from the outside of the chimney structure to any combustible material. This is because in the event of a chimney fire without that space enough heat could be transferred through the masonry to ignite that adjacent combustible material. This risk is made greater through pyrolization which is a process that over time greatly reduces the ignition point of wood. Another very common problem with chimneys like yours is the fact that many times the hearth slab was poured onto wooden forms which were never removed that means that there may be combustible materials in contact with the outside of that clay liner just above where the pipe enters from the stove. This needs to be inspected and addressed if it is there.

 

[gandalf]

I doubt this adds a lot, but here is looking through the hole in the block wall of the basement.



And the camera inside that hole, facing straight up.



So I don't think I was remembering correctly. I thought there was an offset between the flue and the hole in the block wall. It appears to be a straight shot. I also thought I remembered seeing the bottom-most clay tile a few feet above the hole in the block, but don't see it here. This was taken after dark and lighting wasn't the greatest. I'll try again when I have daylight from the top.