Stovepipe clearance of 18" vs. what the stove manufacturer certification plate states?

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It is a bs manual and response. Uncertified single wall pipe needs 18"s of clearance. If they tested it and certified it it would have a certification sticker on the pipe. Just because they tested their stove at those clearances, doesn't mean that the testing cert extends to uncertified single wall pipe. So unless they supplied certified single wall with their stove, with a certification decal on it showing reduced clearances. The single wall pipe that you buy to hook up their stove is still uncertified and requires 18" of clearance.
But appliance manufacturers can test for clearance from single wall pipe for their appliance. They do it all the time for furnaces and they are just ul listed appliances just like wood stoves. And like woodstoves the default is 18" for singlewall unless specified otherwise.
 
I have no real experience/knowledge in that regards. But for stoves this same issue has been discussed at length on another forum I'm a member of and in Canada I'd feel confident in saying that the 18" clearance for single wall should be honoured.
 
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Certs and grey areas aside. If you're looking to safely install with reduced clearances, double wall is the clear choice for safety and performance.
 
That may be an error, examples?
For one it would be none other than the Quad 3100 Millenium
Capture.JPG Capture2.JPG .
Shown as 18.25" to the center.
 
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Can you find any others? I'm confident there are some. It is a manufacturer oversight IMO.

B365 - 4.2.1 Manufacturer’s certified instructions
Certified appliances, accessories, components, and equipment shall be installed in accordance with the
manufacturer’s certified instructions. When a difference exists between the manufacturer’s certified
instructions and the requirements of this Code, the manufacturer’s instructions shall take precedence.
Note: A flue pipe is not considered a component of a certified appliance (see note to Clause 6.4.7).
B365 - 6.4.7

The minimum clearance for a flue pipe adjacent to a combustible surface shall be 450 mm (18 in),
regardless of whether the surface is covered with noncombustible material such as plaster or cement
board. See Figures 3 to 5.
Note: The flue pipe clearances shown on wood stove certification labels are for information purposes only and do not supersede the clearance requirements of this Clause.

In Canada there is no question about this. Ulc s627 is our standard and it is an appliance testing standard, not a flue pipe testing standard. To try to blur the lines of appliance certification to potentially compromise safety is foolish.ymmv in the USA, but I would never recommend installing a single wall flue pipe closer than 18"s to combustibles.
 
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Can you find any others? I'm confident there are some. It is a manufacturer oversight IMO.

B365 - 4.2.1 Manufacturer’s certified instructions
Certified appliances, accessories, components, and equipment shall be installed in accordance with the
manufacturer’s certified instructions. When a difference exists between the manufacturer’s certified
instructions and the requirements of this Code, the manufacturer’s instructions shall take precedence.
Note: A flue pipe is not considered a component of a certified appliance (see note to Clause 6.4.7).
B365 - 6.4.7

The minimum clearance for a flue pipe adjacent to a combustible surface shall be 450 mm (18 in),
regardless of whether the surface is covered with noncombustible material such as plaster or cement
board. See Figures 3 to 5.
Note: The flue pipe clearances shown on wood stove certification labels are for information purposes only and do not supersede the clearance requirements of this Clause.

In Canada there is no question about this. Ulc s627 is our standard and it is an appliance testing standard, not a flue pipe testing standard. To try to blur the lines of appliance certification to potentially compromise safety is foolish.ymmv in the USA, but I would never recommend installing a single wall flue pipe closer than 18"s to combustibles.
Well in canada it is pretty clear but usa it is not. Like i have said because it is a grey area i go with 18" but as far as i can tell by code an appliance manufacturer can reduce clearances
 
I am pretty sure my brother's stove said to the center of the pipe. Dont know the make of the stove right presently.
 
Can you find any others? I'm confident there are some. It is a manufacturer oversight IMO.


Note: The flue pipe clearances shown on wood stove certification labels are for information purposes only and do not supersede the clearance requirements of this Clause..

For who and what information? The fire investigator?
 
Other stove manuals that show reduced clearances for single wall pipe. For me, because I'm interested in the information.
 
Well in canada it is pretty clear but usa it is not. Like i have said because it is a grey area i go with 18" but as far as i can tell by code an appliance manufacturer can reduce clearances

I mainly have posted that in case a Canadian is reading through a thread like this and thinks they have the green light to install at reduced single wall clearances without proper shielding. As for The USA I'll let you guys hash out the details. We know from many code differences that obviously things are more flammable in Canada. ;)

Also in Canada some appliances like furnaces are tested for reduced clearances on single wall stovepipe and they are accepted for installation, it is a different standard then our wood stove testing standard though. I haven't researched it fully enough to understand the exact code differences. But for woodstoves up here it's clear, no grey area.
 
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I'll throw this can of worms out there.

So where a single wall pipe meets a certified ceiling support box, just how close does that single wall get to combustibles? Well under 18"s and right at the ceiling too, near horizontal surfaces instead of the 18"s required all the way up near vertical surfaces.
 
I'll throw this can of worms out there.

So where a single wall pipe meets a certified ceiling support box, just how close does that single wall get to combustibles? Well under 18"s and right at the ceiling too, near horizontal surfaces instead of the 18"s required all the way up near vertical surfaces.
Yeah i know and i have yet to get a good answer from any manufacturer on that yet.
 
I have no real experience/knowledge in that regards. But for stoves this same issue has been discussed at length on another forum I'm a member of and in Canada I'd feel confident in saying that the 18" clearance for single wall should be honoured.
Agreed, the most conservative clearance requirement should be honored.
For one it would be none other than the Quad 3100 MilleniumView attachment 227666 View attachment 227667 . Shown as 18.25" to the center.

Very interesting, That's from the same HHT documentation dept.. They need a review of stove pipe specs. Here is the original Quad Millenium 3100 doc diagram. Note the clearance A.
Screen Shot 2018-07-05 at 10.02.09 AM.png
 
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Some regency stoves do
You are right, the popular F2400 does this too. What does a Regency installer do in this circumstance with a single-wall stove pipe installation? Follow Regency's manual or Ventis's explicit instructions? It would seem that violating the stove pipe mfg. directions would void the pipe warranty and place liability on the installer if any issues arose.
 
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I'll throw this can of worms out there.

So where a single wall pipe meets a certified ceiling support box, just how close does that single wall get to combustibles? Well under 18"s and right at the ceiling too, near horizontal surfaces instead of the 18"s required all the way up near vertical surfaces.


This has been an interesting conversation to follow from a layman's view, and this is also something I have often wondered about.

<------ Very very layman.....
 
Agreed, the most conservative clearance requirement should be honored.


Very interesting, That's from the same HHT documentation dept.. They need a review of stove pipe specs. Here is the original Quad Millenium 3100 doc diagram. Note the clearance A.
View attachment 227668


It is the same dimension but to a different spot. Add 3" for half the pipe and you get the same 18.25"
 
You are right, the popular F2400 does this too. What does a Regency installer do in this circumstance with a single-wall stove pipe installation? Follow Regency's manual or Ventis's explicit instructions? It would seem that violating the stove pipe mfg. directions would void the pipe warranty and place liability on the installer if any issues arose.


How much warranty is on single wall? And there is no liability on an unlisted product is there?
 
Olympia (Ventis) has a 10 yr warranty on their single wall.
 
You are right, the popular F2400 does this too. What does a Regency installer do in this circumstance with a single-wall stove pipe installation? Follow Regency's manual or Ventis's explicit instructions? It would seem that violating the stove pipe mfg. directions would void the pipe warranty and place liability on the installer if any issues arose.
Like i said personally i use double wall. But due to the fact that the pipe is unlisted and is not tested for clearances. While regency assures me their clearances are all tested and verified. It should be safe and to code to follow regencies clearances. Because code only references listed product instrucions to be followed.
 
Olympia (Ventis) has a 10 yr warranty on their single wall.
That is dang good warranty. Not sure what clearance has to do with rusting away but OK. I guess they could use that against you but how would they know how close it was?

I used the DuraBlack. I think I paid $70 with shipping for two 45's and two 2' sections
 
That is dang good warranty. Not sure what clearance has to do with rusting away but OK. I guess they could use that against you but how would they know how close it was?
If there was a fire or even a scorched wall claim.

Ventis's warranty on their double-wall stove pipe is forever, even if the house is sold.
 
You are right, the popular F2400 does this too. What does a Regency installer do in this circumstance with a single-wall stove pipe installation? Follow Regency's manual or Ventis's explicit instructions? It would seem that violating the stove pipe mfg. directions would void the pipe warranty and place liability on the installer if any issues arose.
And as far as liability goes the installer is always the lowest guy on the totem pole. It all fall on us. Which is why i never install stoves or connector pipe to minimum. I always allow atleast an extra inch.

If there was a fire or even a scorched wall claim.

Ventis's warranty on their double-wall stove pipe is forever, even if the house is sold.
Yes but fire or scorching has nothing to do with the warranty
 
And as far as liability goes the installer is always the lowest guy on the totem pole. It all fall on us. Which is why i never install stoves or connector pipe to minimum. I always allow atleast an extra inch.
Agreed. So in this case is that an extra inch over the stove clearance spec or the stove pipe clearance spec? For me, it would be the latter.