Vents on furnace & water heater.

[Buck Hartley, CMI]

Found this on today's inspection. Furnace installed in 2007. Flue looks funny. Cardboard barrier around furnace flue in attic.

[Charley L. Bottger]

Originally Posted by bhartley

Found this on today's inspection. Furnace installed in 2007. Flue looks funny. Cardboard barrier around furnace flue in attic.

To many 90's in it for me looks like crap was the furnace gravity or forced air. 1 inch clearance to combustibles on double wall class B vent pipe. I would recommend the card board be removed even if it was a foot away from the flue simply because someone might knock it against the pipe and leave it there. Recommend metal to keep the insulation back from the flue

[Joe Funderburk, CMI]

The water heater vent pipe has a negative or neutral pitch. To ensure a positive draft, it should rise at one-quarter inch per foot.

The draft hood on the water heater is not seated.

If the cardboard is < 1" from the B-vent flue in the attic, or if the flue is < 1" from anything else combustible (cellulose insulation?), then that's a no no.

[Charley L. Bottger]

Let me ask you this question why should it be considered a combustible hazard on a furnace flue pipe fifteen feet from the furnace where the flue penetrates the roof its still required 1 inch of clearance to combustibles but one can touch the flue pipe with the furnace operating and it will not burn your hand??????

[Joe Funderburk, CMI]

Originally Posted by cbottger

Let me ask you this question why should it be considered a combustible hazard on a furnace flue pipe fifteen feet from the furnace where the flue penetrates the roof its still required 1 inch of clearance to combustibles but one can touch the flue pipe with the furnace operating and it will not burn your hand??????

I don't know where you got the "fifteen" number.

Regarding the 1" rule, ask the manufacturers. It's their standard.

And, I know I've accidentally touched furnace flues during an inspection and it certainly did burn my hand (and once my face).

[Charley L. Bottger]

Originally Posted by jfunderburk

I don't know where you got the "fifteen" number.

Regarding the 1" rule, ask the manufacturers. It's their standard.

And, I know I've accidentally touched furnace flues during an inspection and it certainly did burn my hand (and once my face).

I just made the 15 # up out of my Butt it might be 10 feet makes no difference. The one inch rule is set by the MFG and yes I live by it write up everyone I see. Just asking if you know why if the flue is not hot how can it be a danger there is a reason

[dbucknavich]

Originally Posted by cbottger

I just made the 15 # up out of my Butt it might be 10 feet makes no difference. The one inch rule is set by the MFG and yes I live by it write up everyone I see. Just asking if you know why if the flue is not hot how can it be a danger there is a reason

Charley, I want to say electrolysis (no not hair removal) is a complex process that makes something more flammable over time. Eventually, the combustion point of a product lowers and it takes less and less to ignite it.

[Joe Funderburk, CMI]

Originally Posted by cbottger

I just made the 15 # up out of my Butt it might be 10 feet makes no difference. The one inch rule is set by the MFG and yes I live by it write up everyone I see. Just asking if you know why if the flue is not hot how can it be a danger there is a reason

The manufacturers cover their rear end just like home inspectors do. They set standards with plenty of safety factor built in.

[Charley L. Bottger]

Originally Posted by jfunderburk

The manufacturers cover their rear end just like home inspectors do. They set standards with plenty of safety factor built in.

Now you are thinking give me the safety factor I have had people ask me that same question if it is not hot why does it have to have clearance. I have a answer for them

[Charley L. Bottger]

Originally Posted by dbucknavich

Charley, I want to say electrolysis (no not hair removal) is a complex process that makes something more flammable over time. Eventually, the combustion point of a product lowers and it takes less and less to ignite it.

You got that part right something can happen over time

[dbucknavich]

Originally Posted by cbottger

You got that part right something can happen over time

Which is why it is an issue.

[Charley L. Bottger]

Originally Posted by dbucknavich

Which is why it is an issue.

That is correct but what is the issue. I'm not easy tonight not giving it up

[dbucknavich]

Originally Posted by cbottger

That is correct but what is the issue. I'm not easy tonight not giving it up

Haha. Friggin Charley. The issue is the whole clearance thing. Since you're not giving up, I definitely will. I can't even tell how far that cardboard is away from the vent. I was just describing a process I heard in school about why things (if within clearances) can be problematic, and the actual process of why that occurs. But I would say a product like cardboard is most unconventional in that application and would raise doubt in my mind, considering its likelihood to combust.

There, I think that satisfies me without challenging you. I hope.

[Joe Funderburk, CMI]

Originally Posted by dbucknavich

Charley, I want to say electrolysis (no not hair removal) is a complex process that makes something more flammable over time. Eventually, the combustion point of a product lowers and it takes less and less to ignite it.

Electrolysis??? There are only 2 definitions of that word, and neither makes sense in relation to your sentence.

1. Physical Chemistry. the passage of an electric current through an electrolyte with subsequent migration of positively and negatively charged ions to the negative and positive electrodes.
2. the destruction of hair roots, tumors, etc., by an electric current.

[dbucknavich]

Originally Posted by jfunderburk

Electrolysis??? There are only 2 definitions of that word, and neither makes sense in relation to your sentence.

1. Physical Chemistry. the passage of an electric current through an electrolyte with subsequent migration of positively and negatively charged ions to the negative and positive electrodes.
2. the destruction of hair roots, tumors, etc., by an electric current.

Joe,

I know.
I gave up trying to find the exact term and went ahead with the post, but I swear it was either electrolysis or something very similar. That's why I said "I want to say". If I find it I'll let you know. I have it somewhere in the bookcase. Maybe Pyrolysis.