Thread: Water heater (combustion air)

The water heater is located in a designated closet in master bedroom (1997 MFG home factory built this way) The flue pipe is different than I have seen before. I am not sure if the flue pipe is designed to provide combustion air also, or if it's just to provide clearance from combustibles. This is the first time I have come across and installation like this, any help would be much appreciated.

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Originally Posted by Trent Tarter

The water heater is located in a designated closet in master bedroom (1997 MFG home factory built this way) The flue pipe is different than I have seen before. I am not sure if the flue pipe is designed to provide combustion air also, or if it's just to provide clearance from combustibles. This is the first time I have come across and installation like this, any help would be much appreciated.

TT: Who is the manufacturer? Do you have more photos?

The manufacture is State. My concern is combustion air, the closet has no vent openings to provide combustion air unless it is coming from the flue pipe, which I would amagine it is. The water heater is the original factory installed unit.

Originally Posted by Trent Tarter

The water heater is located in a designated closet in master bedroom (1997 MFG home factory built this way) The flue pipe is different than I have seen before. I am not sure if the flue pipe is designed to provide combustion air also, or if it's just to provide clearance from combustibles. This is the first time I have come across and installation like this, any help would be much appreciated.

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The water heater could ( should ) have a Minimum 5 inch Dia. hole in the floor (usually under the burner.)
* solid door construction for combustion air.

There are no holes in the floor, unless the water heater is sitting on top of one?

Originally Posted by Trent Tarter

The manufacture is State. My concern is combustion air, the closet has no vent openings to provide combustion air unless it is coming from the flue pipe, which I would amagine it is. The water heater is the original factory installed unit.

This should apply:
http://www.statewaterheaters.com/lit...185874-001.pdf

What is the unit's age?
Is it an FVIR?

I don't see any provisions in State's instructions to eliminate the draft hood as has been done in your photo. I also do not see any language for departure from orthodox combustion air sources.

I am not familiar with any combination vent and combustion air piping for gas appliances other than for direct vent.

Wait on the wrench-slingers to arrive and pontificate.

Originally Posted by Trent Tarter

There are no holes in the floor, unless the water heater is sitting on top of one?

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Yes.

See Page 6 for illustration.
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Thanks Billy,
Now it all makes sense, the combustion air opening is most likely below the unit. However I would have to go back and look in the crawlspace to verify that. I guess I know I'm going to be doing later today, the place is only about 5 minutes away and has an outside CSA. Thanks for the help.

Originally Posted by Trent Tarter

I'm going to be doing later today, the place is only about 5 minutes away and has an outside CSA. Thanks for the help.

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Maybe someone can ID the Draft Hood.
* or lack there of.
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If you could tell me the Model # of the unit I can tell you if it is getting is combstion air from somewhere else.

Looking at that vent it looks like there was a direct vent unit installed originally and some one replaced the heater with a standard unit which is not the correct. The model # by state for a direct vent unit would start with GS6 and end with YBDS. I do wish there was more of overall shot showing all of the vent piping.

From what I can tell from the picture the vent piping was from Bradford white. http://www.bradfordwhite.com/images/...eets/105-B.pdf The direct vent units bring in fresh air from the larger pipe "INTO" the heater just just above it. As the exhaust gas is vented out the 3" pipe.

I don't have the model number. It appears to the original unit, same year as the home. Another concern was the slight smell of gas when the closet door was opened. The smell quickly dissipated and I could not find any leaks at gas supply lines or at the unit. I am going over to verify that there is a combustion air vent below the unit in crawlspace. I have never seen venting like this with out a draft hood.

Originally Posted by Trent Tarter

I don't have the model number. It appears to the original unit, same year as the home. Another concern was the slight smell of gas when the closet door was opened. The smell quickly dissipated and I could not find any leaks at gas supply lines or at the unit. I am going over to verify that there is a combustion air vent below the unit in crawlspace. I have never seen venting like this with out a draft hood.

AS I pointed out direct vent units do not use a draft hood, the ones with the hole in the floor still use a draft hood.

Originally Posted by Ron Hasil

Looking at that vent it looks like there was a direct vent unit installed originally and some one replaced the heater with a standard unit which is not the correct. The model # by state for a direct vent unit would start with GS6 and end with YBDS. I do wish there was more of overall shot showing all of the vent piping.

From what I can tell from the picture the vent piping was from Bradford white. http://www.bradfordwhite.com/images/...eets/105-B.pdf The direct vent units bring in fresh air from the larger pipe "INTO" the heater just just above it. As the exhaust gas is vented out the 3" pipe.

Ron,

State also makes a direct vent water heater similar to that Bradford-White one, but not approved for use in manufactured homes.

No there was never a direct vent unit installed. The water heater is located near the center of the home and it's a triple wide. I did however go back to take a look in the crawlspace and sure enough there is a combustion air pipe below the unit. My concern now is proper drafting and venting.

Trent, where is the cold water supply into the water heater?

Originally Posted by Trent Tarter

No there was never a direct vent unit installed. The water heater is located near the center of the home and it's a triple wide. I did however go back to take a look in the crawlspace and sure enough there is a combustion air pipe below the unit. My concern now is proper drafting and venting.

Did you grab the model number of the unit?

Originally Posted by neal lewis

Trent, where is the cold water supply into the water heater?

NL: The water supply enters through the sides of these units.

Cold water supply is at the side of the unit.

Is there an echo in here?

I thought in some jurisdictions, a seperate combustion air vent was not req'd for HWT's in closets (by themselves) IF they were less than 40,000 btu's. I'd be concerned about it being located in the closet of a sleeping room though.

That fitting on top of the hwt is not for the prv is it ?

You need to correlate the venting with the listed instructions. There are stampings on the right side of the outer casing of the vent as seen in the second pic. If you can find documentation this venting is approved for this unit in this application then it should be allowable. If not, it would need to be called out.

I'm guessing this is a singlewalled vent with a special close clearance adapter.

Take pics of the rating plate, vent markings, MUA, etc. BTW, if pulling MUA from under the home, the skirt must have prescribed ventilation openings as well. The intake would need to be accessible for inspection and cleaning the screen. I'd use a mirror to peek up the concentric ring of that vent to see if it isn't an extension of the draft hood.
Bob

It would help to identify the combustion air source (or lack thereof) if we had a photo of the lower section of the tank. The draft hood on top looks abit homemade???

Originally Posted by Billy Stephens

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See Page 6 for illustration.
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Originally Posted by Trent Tarter

I did however go back to take a look in the crawlspace and sure enough there is a combustion air pipe below the unit.

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Originally Posted by Robert Dalga

It would help to identify the combustion air source (or lack thereof) if we had a photo of the lower section of the tank. The draft hood on top looks abit homemade???

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Robert.
attachment is of page 6.
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