Water heater penetrations

[KristenJensen]

(El Paso, TX) I have a 13-year-old 40g gas water heater in my hallway closet. There are two vents, one for flue gases and the other fresh air intake. Is there a product that integrates these so I have a single roof penetration?

The door into the 27” x 23” closet has very little space between the floor and the bottom of the door (tight-ish seal).

The roof needs to be replaced (25 y/o T-Lock shingles in poor condition) and I’m looking to reduce roof penetrations during this. I may even do a standing seam metal roof for solar and want to maximize available square footage for panels.

I am also considering installing an electric water heater to fully eliminate penetrations.

Looking for opinions/suggestions from this group. Thank you in advance.

-Kristen

 

[Reach4]

I am also considering installing an electric water heater to fully eliminate penetrations.

You will still need a plumbing drain line vent.

 

[Sponsor]

 

[Breplum]

The Uniform Mechanical Code (fairly international in scope and acceptance) only requires the high and low combustion air openings or ducts to vent into free flowing air spaces like crawl space and ventilated attic, without requirement to penetrate a roof.
When venting into an attic, the requirement is to be above any insulation far enough that it can't clog the vent.
There is supposed to be an actual roof jack/flashing with a minimum rise of 18" off the roof and in fact must not have intake within 10' or rise to 3' above any intakes/vents.
Looks like your vents are non-conforming and outright dangerous as carbon monoxide can go right back into the closet and cause a truly dangerous life threatening situation.

 

[KristenJensen]

The Uniform Mechanical Code (fairly international in scope and acceptance) only requires the high and low combustion air openings or ducts to vent into free flowing air spaces like crawl space and ventilated attic, without requirement to penetrate a roof.
When venting into an attic, the requirement is to be above any insulation far enough that it can't clog the vent.
There is supposed to be an actual roof jack/flashing with a minimum rise of 18" off the roof and in fact must not have intake within 10' or rise to 3' above any intakes/vents.
Looks like your vents are non-conforming and outright dangerous as carbon monoxide can go right back into the closet and cause a truly dangerous life threatening situation

This makes a lot of sense. Thank you for the information.
I don't have a crawl space/basement, and the attic is pretty tight (but doable). Are there rules around undercutting the door (1") or installing a louver panel to allow conditioned house air into the closet to allow enough air flow and eliminate the 8" opening completely? This would just leave the flue pipe penetration.

 

[KristenJensen]

You will still need a plumbing drain line vent.

Wow, I was unaware. Thank you for mentioning.

 

[Breplum]

Most jurisdictions do not allow louvered doors for combustion air on interiors (ostensibly because dummies can remove the doors and put back solid doors and foul up combustion air situation.
The code requires high and low combustion air. The area required for each opening related to unconfined space is min. 100 sq. in. openings, one in upper 12" and one in lower 12in.. So above the door in sheetrock.
If you did an undercut in the door, then you would have to eliminate the attic or roof opening since it would allow air infiltration into the dwelling, like a permanently open window.

 

[GReynolds929]

The fresh air intake should not be that close to the exhaust flue. You can pull CO into the house.

 

[Breplum]

The fresh air intake should not be that close to the exhaust flue. You can pull CO into the house.

I did state same.

 

[Master Plumber Mark]

Just throw in an electric water heater and forget about it

 

[Fitter30]

Rheem makes a direct vent that might work.
www.rheem.com/product/rheem-professional-classic-series-direct-vent-prog40-36n-rh62-dv/

 

[Master Plumber Mark]

you could also just throw in a 50 gallon power vent and put it out the side of the house instead of the roof
all it takes is a puny 2 inch pvc vent which can be run up to 60 feet across....
does not need an air intake neither ...

 

[Reach4]

you could also just throw in a 50 gallon power vent and put it out the side of the house instead of the roof
all it takes is a puny 2 inch pvc vent which can be run up to 60 feet across....
does not need an air intake neither ...

I have seen a power vent WH. I noticed it looked like it has provision for an optional outside air intake. Was that built to make an external intake an option?

 

[Master Plumber Mark]

I have seen a power vent WH. I noticed it looked like it has provision for an optional outside air intake. Was that built to make an external intake an option?

The common power vent gas wh does not need a air intake from the outside.... it just comes standard that way

They do make a unit that takes in air from the outside but they are very expensive and very, very rare and hard to
find .... I tried to get one for some cusomer one time in Bradford White and it was going to take well over a month to specioal
order and it was costing 3500 or more...

The common power vent unit works fine without any extra air... Also you have a vent already going up into the attic
which can be cut off under the roof line which would add extra air into the room if you wanted to do this...

 

[Slomoola]

My house has two 40g gas fired tanks. The one in the middle is in a small closet. Has one flue pipe that goes through the roof. Have two vent pipes for fresh air. Those simply go into the attic for combustion air. Been working for decades. Even have a smoke and CO detector in the closet. Never goes off knock on wood.