8" collar reduced to 6" and back to 8"

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Scoturq

New Member
Feb 6, 2023
2
Washington
Found this great forum while searching out a concern. Seen a few similar discusions but mine is a bit different. We have a big Blaze King King that has been working great except for a bit of smoke released into house when reloading. Recently noticed a few cracks and rough spots on the interior stove pipe and decided to have a chimney company replace the bad sections.

Stove is mounted in the corner and had a 8"x30" pipe going up to a 90 elbow and then a 8"x20" horizontal going to wall. Right before exiting there is a 8" to 6" reducer. Once outside its straight up 20 feet and all 8".

When installers showed up they replaced everything on the inside with 6" pipe and an 8" to 6" reducer at the stove collar. When i questioned them about this they said they wondered why there was a reducer in the first place. I called Blaze king who said I would likely have draft issues that could be alleviated if the 6" was double wall and they used a couple 45's instead of the 90. Pipe they used is Excel Prime single wall. They suggest I have a fire, see how draft is and call them if need to replace with 45's. I have not done the first fire yet as I wanted to do some due dilligence since quote included parts for 8" instead of what was installed.

Hoping some of the experts here can chime in on best case/worst case before I test things out, Also wondering about concerns with code since i read some comments here not reducing an 8" stove at the stove.

Glad to be part of this group and look forward to hearing your thoughts.

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I don’t see how it wouldn’t choke draft.

I’m sure it’ll work, but you may have issues opening the door to reload.

If you paid for 8” parts, I’d get 8” parts.
 
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Double-wall stovepipe is recommended for this stove. If there is an 8" liner then why has this been reduced to 6"?
 
Found this great forum while searching out a concern. Seen a few similar discusions but mine is a bit different. We have a big Blaze King King that has been working great except for a bit of smoke released into house when reloading. Recently noticed a few cracks and rough spots on the interior stove pipe and decided to have a chimney company replace the bad sections.

Stove is mounted in the corner and had a 8"x30" pipe going up to a 90 elbow and then a 8"x20" horizontal going to wall. Right before exiting there is a 8" to 6" reducer. Once outside its straight up 20 feet and all 8".

When installers showed up they replaced everything on the inside with 6" pipe and an 8" to 6" reducer at the stove collar. When i questioned them about this they said they wondered why there was a reducer in the first place. I called Blaze king who said I would likely have draft issues that could be alleviated if the 6" was double wall and they used a couple 45's instead of the 90. Pipe they used is Excel Prime single wall. They suggest I have a fire, see how draft is and call them if need to replace with 45's. I have not done the first fire yet as I wanted to do some due dilligence since quote included parts for 8" instead of what was installed.

Hoping some of the experts here can chime in on best case/worst case before I test things out, Also wondering about concerns with code since i read some comments here not reducing an 8" stove at the stove.

Glad to be part of this group and look forward to hearing your thoughts.

View attachment 309276
Had first fire yesterday and draft seemed to be ok. Catalytic kicked in after 20 minutes and no smoke leaking. I was mistaken about 8" on the outside of house. Looks like it is triplewall stainless duravent so 8" exterior and 6" interior. The 8" was only the vertical exit from stove and horizontal to wall before reduction to 6". Little bit of smoke came out when reloading but that has always been a problem (assume this is because not 8" everywhere) Clearance between ceiling and pipe is just under 18" and has a vent directly above that vents to upstairs bathroom floor.

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