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

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Yes The insert manufacturer tests their unit in one or two fireplaces without any set standatd to test to. Yet you are ok with ignoring the fireplace manufacturer who says dont do it. But you question their stated clearances which have an established testing procedure to follow??? And would rather adhere to a generic clearance set by code which in all other cases are over ridden by manufacturers specs. What about if the pipe is used on a furnace which only requires 6" of clearance to single wall?
Give it a rest. You assume way too much and no one ever mentioned furnace piping in this thread.
 
Give it a rest. You assume way too much and no one ever mentioned furnace piping in this thread.
No but if you say the specs for single wall over ride appliance specs why would it be different for a furnace. I am assuming nothing. Manufacturers specs over ride code and the only reason sny single wall pipe says 18" (which many dont) is the generic unlisted stove clearance requirement. I just dont understand the reason you apply the rules differently in some situations.
 
Response from Heatilator support -
We do not manufacture the pipe. If there are different clearances for that pipe then you must follow per their instructions. In the manual it does state to * SEE PIPE MANUFACTURERS CLEARANCES - NOT TESTED*

**********************

DuraBlack -
IMPORTANT DuraBlack must be installed with at least an 18”" Clearance to Combustibles

Excel -
EXCELPrime 18”" Clearance Stove Pipe - 18”" clearance minimum - A MAJOR CAUSE OF CHIMNEY RELATED FIRES IS FAILURE TO MAINTAIN REQUIRED CLEARANCES (AIR SPACE) TO COMBUSTIBLE MATERIALS. IT IS OF UTMOST IMPORTANCE THAT THIS CONNECTOR BE INSTALLED ONLY IN ACCORDANCE WITH THESE INSTRUCTIONS.

Selkirk -
SAFETY - Saf-T Pipe must be installed with a minimum of 18”" clearance to any combustible surfaces or materials

IMPORTANT: A major cause of vent related fires is failure to maintain required clearances (air spaces) to combustible materials. It is of the utmost importance this Saf-T Pipe be installed only in accordance with these instructions.

Ventis single-wall
Screen Shot 2018-06-25 at 10.26.07 AM.png Screen Shot 2018-06-25 at 10.24.23 AM.png
 
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Response from Heatilator support -
We do not manufacture the pipe. If there are different clearances for that pipe then you must follow per their instructions. In the manual it does state to * SEE PIPE MANUFACTURERS CLEARANCES - NOT TESTED*

**********************

DuraBlack -
IMPORTANT DuraBlack must be installed with at least an 18”" Clearance to Combustibles

Excel -
EXCELPrime 18”" Clearance Stove Pipe - 18”" clearance minimum - A MAJOR CAUSE OF CHIMNEY RELATED FIRES IS FAILURE TO MAINTAIN REQUIRED CLEARANCES (AIR SPACE) TO COMBUSTIBLE MATERIALS. IT IS OF UTMOST IMPORTANCE THAT THIS CONNECTOR BE INSTALLED ONLY IN ACCORDANCE WITH THESE INSTRUCTIONS.

Selkirk -
SAFETY - Saf-T Pipe must be installed with a minimum of 18”" clearance to any combustible surfaces or materials

IMPORTANT: A major cause of vent related fires is failure to maintain required clearances (air spaces) to combustible materials. It is of the utmost importance this Saf-T Pipe be installed only in accordance with these instructions.
Ok well i have to question all of hhts clearances then. Because if they dont test their stated clearances how do they justify them? When i talked to our regency rep about the issue they said yes the clearances were tested using approved ul testing procedures and that legally they cannot publish and clearances which are not tested because they are selling a ul listed product.

In comparison durablack excellprime saf-t pipe ventis single wall and most others are not ul listed and all of their instructions refer to the 18" requirement as stated in nfpa 211. And we all know nfpa 211 clearances are overridden by manufacturers instructions.

Now if heatilator says their clearances are dont overide then clearly they dont in this case. But then why did they publish that manual with those clearances?
 
Response from Heatilator support -
We do not manufacture the pipe. If there are different clearances for that pipe then you must follow per their instructions. In the manual it does state to * SEE PIPE MANUFACTURERS CLEARANCES - NOT TESTED*

**********************

DuraBlack -
IMPORTANT DuraBlack must be installed with at least an 18”" Clearance to Combustibles

Excel -
EXCELPrime 18”" Clearance Stove Pipe - 18”" clearance minimum - A MAJOR CAUSE OF CHIMNEY RELATED FIRES IS FAILURE TO MAINTAIN REQUIRED CLEARANCES (AIR SPACE) TO COMBUSTIBLE MATERIALS. IT IS OF UTMOST IMPORTANCE THAT THIS CONNECTOR BE INSTALLED ONLY IN ACCORDANCE WITH THESE INSTRUCTIONS.

Selkirk -
SAFETY - Saf-T Pipe must be installed with a minimum of 18”" clearance to any combustible surfaces or materials

IMPORTANT: A major cause of vent related fires is failure to maintain required clearances (air spaces) to combustible materials. It is of the utmost importance this Saf-T Pipe be installed only in accordance with these instructions.

Ventis single-wall
View attachment 227477
View attachment 227476
Ahhh, it looks like our companies abc & xyz pipe manufactures are safe.
 
Now if heatilator says their clearances are dont overide then clearly they dont in this case. But then why did they publish that manual with those clearances?
Very good question. I asked if HHT would assume liability if there was an issue and got no response. Ventis states it most clearly. When there is conflict between the two clearance requirements always use the larger clearance distance.
 
Nope. Only under one specific measurement does it have an asterisk and state not tested, see pipe manufacturer specs. I dont accept their response as valid and may sue for return of the appliance.

I bought the appliance due to its advertised clearances.
 
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I bought the appliance due to its advertised clearances.
To avoid the extra legal fee's why don't you just install double wall black pipe (minimum clearance is 6" to combustible wall) then you can honor the stoves minimum clearance.
Plus the advantages of double wall pipe are hotter flue gases due to less radiation, hotter flue gases mean less of a chance of creosote build up which is a win.
 
Yes, the hotter flue gases will help it draft better too and the interior of double-wall stove pipe is stainless steel. It should last longer.
 
The response from HHT was bullspit. Only on the pipe to ceiling measurement for horizontal venting does it say *see pipe manufacturer not tested"

It CLEARLY say SINGLE WALL - 12 Inches. I think UL should be notified about this.
 
Very good question. I asked if HHT would assume liability if there was an issue and got no response. Ventis states it most clearly. When there is conflict between the two clearance requirements always use the larger clearance distance.
Yes it does say that. But that is in a manual for an unlisted product. Which legally doesnt mean much. But clearly there is a grey area and lots of conflicting info which is why like i said i always just go with double wall under 18". I am pretty sure it is fine by code to go by the stoves stated clearance. But for my peice of mind and to cover my butt i go on the side of caution.
 
The response from HHT was bullspit. Only on the pipe to ceiling measurement for horizontal venting does it say *see pipe manufacturer not tested"

It CLEARLY say SINGLE WALL - 12 Inches. I think UL should be notified about this.
I agree their response is bs. If they didnt test that clearance where did it come from?
 
Very good question. I asked if HHT would assume liability if there was an issue and got no response. Ventis states it most clearly. When there is conflict between the two clearance requirements always use the larger clearance distance.
You know no one is going to voluntarily assume liability.
 
Another "engineer" talking out his rear vent. Why do many stoves say 18.25" to the CENTER of the pipe. Big name stoves to boot.
 
To avoid the extra legal fee's why don't you just install double wall black pipe (minimum clearance is 6" to combustible wall) then you can honor the stoves minimum clearance.
Plus the advantages of double wall pipe are hotter flue gases due to less radiation, hotter flue gases mean less of a chance of creosote build up which is a win.

LOL. Id just put a heat shield on the back of the up section. It hits a 45 angling away from wall at about 2 feet from the collar. Has anyone ever considered that using double wall for no real reason may contribute to excess draft and runaway stoves?
 
LOL. Id just put a heat shield on the back of the up section. It hits a 45 angling away from wall at about 2 feet from the collar. Has anyone ever considered that using double wall for no real reason may contribute to excess draft and runaway stoves?
I haven't considered that, then again my stack height is only about 18ft (about 3ft higher than the minimum height for my stove) perhaps someone with a chimney height into the high 20's or 30ft may need to think of that, but then again the flue gases might cool off and creosote buildup is the bigger issue.
 
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Always unintended consequences arent there!
 
I agree their response is bs. If they didnt test that clearance where did it come from?
The "didn't test clearance" is for dimension H * which is the pipe to ceiling clearance. It has nothing to do with the stove's flue collar to rear wall clearance (dimension A).
Screen Shot 2018-06-25 at 1.59.37 PM.png
 
The "didn't test clearance" is for dimension H * which is the pipe to ceiling clearance. It has nothing to do with the stove's flue collar to rear wall clearance (dimension A).
View attachment 227480
Ok so does that mean they did test the clearance in question?
 
LOL. Id just put a heat shield on the back of the up section. It hits a 45 angling away from wall at about 2 feet from the collar. Has anyone ever considered that using double wall for no real reason may contribute to excess draft and runaway stoves?
Not really unless the flue system is already so tall that this might be an issue anyway.
 
Ok so does that mean they did test the clearance in question?
Whether they tested wall temps behind the single wall pipe at 12" is a question for Heatilator. I asked for this question to be escalated to a supervisor and that is when I got the BS response. Regardless, I stand by the good advice given by Ventis.
 
Whether they tested wall temps behind the single wall pipe at 12" is a question for Heatilator. I asked for this question to be escalated to a supervisor and that is when I got the BS response. Regardless, I stand by the good advice given by Ventis.
Next time i talk to olympias engeneer i will have to ask him. I just dont see how the untested clearences on an unlisted product could over ride the tested clearances on a listed product according to code.
 
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.
 
Many stove manuals say 18" to the CENTER of the pipe for single wall.