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Ken Amelin
09-15-2016, 06:18 PM
This is a vent connection for a gas water heater. It looks like when they replaced the heater it was too high to install a draft hood at the heater vent outlet, so they made a solid connection to heater and installed a draft vent hood (box with opening on bottom) in the middle of the run.

Never saw this before. #1 Is it safe? #2 Is it legal?

ROBERT YOUNG
09-16-2016, 03:01 AM
Direct venting.
Appears to be a gas water boiler as well.
Are all vents connected entering a chimney?
Typical.


Types of venting.
Atmospheric - with a draft hood.
Direct vent - no draft hood.
Power vent . mechanically assisted atop the water heater.

Lon Henderson
09-16-2016, 06:07 AM
I don't think this is legal. The draft hood provides means for mixing of room air into the combustion gases to create the proper dilution of the flue gases that is required for exhaust of the flue gases.

ROBERT YOUNG
09-16-2016, 07:21 AM
Morning Lon.
I am not disputing that a draft hood is required when required in atmospheric NG venting of combustible gasses.

IMO, the OP is hypothesizing a draft hood was present by saying the venting was lowered.
However, if that is the case it would not meet the manufacturer's venting installation recommendations and raise heath and safety concerns.

I should have rephrased my question.

The image of the venting restricts what type of venting should be in place.
Any others photos and angles?

Jerry Peck
09-16-2016, 07:28 AM
The venting is incorrect, there is no draft hood, no 1 foot rise before the horizontal turn at the elbow, etc.

ROBERT YOUNG
09-16-2016, 07:32 AM
If you look at the top of the WH case there does not appear to be manufactured holes to accept a draft hood.
32944

Although it does appear suspect for direct venting attachment there are no indications a draft hood was present.

The below image is a RHEEM direct vent NG water heater.
32945

Jerry Peck
09-16-2016, 09:12 AM
If you look at the top of the WH case there does not appear to be manufactured holes to accept a draft hood.
32944

Although it does appear suspect for direct venting attachment there are no indications a draft hood was present.

The below image is a RHEEM direct vent NG water heater.
32945

In which case, and as I said:


The venting is incorrect ...

A direct vent does not use a Type B gas vent.

The question of 'how much and what is wrong with the venting' cannot be fully answered without additional information: what type of water heater is it (natural draft, direct vent, fan-assisted, etc; what manufacturer; model; etc.

Showing us a photo as was shown results is suppositions as to what "might" be wrong ... with what the commenter "sees" in the photos.

Rules of thumb (as is a common term):
- 1) take photos of the nameplate, making sure to get the manufacturer, the model number, size, btu/watts rating, date of manufacture, etc.
- 2) take close photos and distance photos to show what is being looked at and the what the entire picture is like
- with digital cameras, there is no such thing as taking 'too many' photos - there is no cost involved, once back at your office an after the report is finished, the photos you don't want can be deleted ... poof! ... and they are gone.

ROBERT YOUNG
09-16-2016, 11:13 AM
In which case, and as I said:



A direct vent does not use a Type B gas vent.

I was not implying it did.



The question of 'how much and what is wrong with the venting' cannot be fully answered without additional information: what type of water heater is it (natural draft, direct vent, fan-assisted, etc; what manufacturer; model; etc.

I concur. I mentioned the manufacturer installation and venting methods are required.



Showing us a photo as was shown results is suppositions as to what "might" be wrong ... with what the commenter "sees" in the photos.
It also supports the suppositions of correct installations. The some may agree while other not rule.;)



Rules of thumb (as is a common term):
- 1) take photos of the nameplate, making sure to get the manufacturer, the model number, size, btu/watts rating, date of manufacture, etc.
- 2) take close photos and distance photos to show what is being looked at and the what the entire picture is like
- with digital cameras, there is no such thing as taking 'too many' photos - there is no cost involved, once back at your office an after the report is finished, the photos you don't want can be deleted ... poof! ... and they are gone.
I concur. Rules of thumb should drive an assessment.
It would be useful to have the manufacturer's name, model number and serial number.

Ken Amelin
09-16-2016, 01:10 PM
I was not implying it did.




I concur. I mentioned the manufacturer installation and venting methods are required.



It also supports the suppositions of correct installations. The some may agree while other not rule.;)



I concur. Rules of thumb should drive an assessment.
It would be useful to have the manufacturer's name, model number and serial number.

Here's the nameplate data - nothing special - run of the mill bradford white.
Also, here's what I was trying to describe as the draft hood (device). it is a metal box in the middle of the vent pipe with the bottom of the box open to the room.

Keith Winston
09-16-2016, 01:30 PM
Direct venting.

Types of venting.
Atmospheric - with a draft hood.
Direct vent - no draft hood.
Power vent . mechanically assisted atop the water heater.

This is NOT what Direct Vent means. If your appliance is rated for atmospheric venting (i.e. barometric damper, or draft hood), you can't just take it outdoors "directly", and you definitely can't do so with a big uncontrolled hole in the venting system. Definition from IRC:
Direct-Vent Appliance: A fuel-burning appliance with a sealed combustion system that draws all air for combustion from the outside atmosphere and discharges all flue gases to the outside atmosphere."

When in doubt check appliance specs/installation instructions.

ROBERT YOUNG
09-16-2016, 01:45 PM
Here's the nameplate data - nothing special - run of the mill bradford white.
Also, here's what I was trying to describe as the draft hood (device). it is a metal box in the middle of the vent pipe with the bottom of the box open to the room.
Here is a PDF from Bradford White for their Gas fired water heaters.
http://www.bradfordwhite.com/sites/default/files/product_literature/238-44219-00G.pdf

2006.
10 YEARS OLD.

12" inch vertical rise is required.
The vent pipe looks disconnected at the base.

Bradford White manufactures a DIRECT-VENT SERIES.
I am writing 2 reports.
others will likely chimney in.

Draft hoods.
Water heater draft hood32948Boiler draft hood 32949

The galvanized box in the vent you point at in red, any electrical mechanical connection?

Jerry Peck
09-16-2016, 02:56 PM
It also supports the suppositions of correct installations.

Robert,

I'm not disputing the above ... okay ... YES I AM! :p ;)

There is nothing I see in that photo which "supports the suppositions of correct installations". :brick: :peep: :pop2:

ROBERT YOUNG
09-16-2016, 03:35 PM
Robert,

I'm not disputing the above ... okay ... YES I AM! :p ;)

There is nothing I see in that photo which "supports the suppositions of correct installations". :brick: :peep: :pop2:

Saying something might be wrong infers some things "might" be right.
:hand:, Is everything wrong:confused:
:pop2:

Jerry Peck
09-16-2016, 05:19 PM
Saying something might be wrong infers some things "might" be right.

Nope.

Saying that something might be wrong infers that AT LEAST "something" might be wrong, that, potentially, "everything" could be wrong, and that, "potentially" something "might" not be wrong, but that is not the inference, that is a left over possibility ... not an inference. :p :focus:

ROBERT YOUNG
09-16-2016, 05:55 PM
Nope.

Saying that something might be wrong infers that AT LEAST "something" might be wrong, that, potentially, "everything" could be wrong, and that, "potentially" something "might" not be wrong, but that is not the inference, that is a left over possibility ... not an inference. :p :focus:

:yield:

What is wrong with the HW venting cannot be fully answered without additional information.

John Kogel
09-16-2016, 06:16 PM
If there is ever an issue with that water heater, leaking fumes or back drafting or both, the home owner's insurance company will most likely refuse to pay up.

Somebody was clever to devise an alternative to the manufacturer's draft hood, but it is wrong and it needs repair, for that reason if no other.

They can close off the existing connection to the chimney and cut a hole higher up. The masonry chimney needs a metal liner with a diameter that is adequate without being too large, probably 4 or maybe 5 inches.

Mark Reinmiller
09-16-2016, 06:57 PM
The type of draft hood shown in the photo is a type that has been used long ago for boilers. It was probably approved for some uses. But, I agree with Jerry that it would not meet manufacturer'so requirements and without proper vertical rise back drafting may occur.

Jerry Peck
09-16-2016, 07:58 PM
What is wrong with the HW venting cannot be fully answered without additional information.

Type of water heater - direct venting or natural draft is one thing we don't know and which completely alters the venting.

Shown is Type B gas vent, with no draft hood at the water heater, and no one foot rise - which are all wrong for a natural draft vented water heater.

If it is direct vent, using Type B gas vent, and not sealed at the water heater and all the out - which are all wrong for a direct vented water heater.

ROBERT YOUNG
09-17-2016, 12:33 AM
Type of water heater - direct venting or natural draft is one thing we don't know and which completely alters the venting.

Shown is Type B gas vent, with no draft hood at the water heater, and no one foot rise - which are all wrong for a natural draft vented water heater.

If it is direct vent, using Type B gas vent, and not sealed at the water heater and all the out - which are all wrong for a direct vented water heater.

I agree with all points.
Not enough information.

I do not see any manufactured, or other penetration openings that would indicate a draft hood was present.

ROBERT YOUNG
09-17-2016, 05:49 AM
In my first post I am not saying this setup is typical.

I agree with/on all points colleagues are making BUT, not enough information.

I am answering the OP questions.
I am not going to guess.

The OP questions and observation.

Observation so far.
1: This is a vent connection for a gas water heater.
Hypothesis: a. It looks like when they replaced the heater it was too high to install a draft hood at the heater vent outlet,
Hypothesis: b. so they made a solid connection to heater and installed a draft vent hood (box with opening on bottom) in the middle of the run.

Ken , A draft hood would be mounted above the fuel tube / heat exchanger.

As well; I have seen a setup similar to this. The vent material was disimular but it was compliant to the OP concerns as pointed out my a qualified plumber. Liability exchanged hands.

Pass on your liability. 1: Recommend a bonded/licensed/certified/qualified technician or tradesperson evaluate the venting and connections. 2: That the client act upon any recommendations therein.

More Questions:
#1 Is it safe?
(Likely not but appears to have operated to a safety margin where no one has been effected for 10 years) I see no puff back or backdraft soot at the connection or top of the WH bonnet.
#2 Is it legal?
( Is it compliant with the manufacturer's installation instructions? Is it code compliant for/with venting combustible gasses?
I doubt either.

I do not see any manufactured, or other mechanical damage penetrations indicating a draft hood was ever present.
The unit is 11 years old. It has been or is suspect that long..

Jerry Peck
09-17-2016, 06:35 AM
I do not see any manufactured, or other penetration openings that would indicate a draft hood was present.

Sometimes there is just one hole, that hole could be on the backside and not visible in the photo.

Lon Henderson
09-17-2016, 07:07 AM
The photo gives us enough information to know that this is installed incorrectly whether natural or direct. And to Ken's initial question, the draft box does not "fix" this improper installation.

Jim Luttrall
09-17-2016, 07:44 AM
It is wrong for all the reasons mentioned.

It "MAY" work just fine but it is not setup according to its listing so no matter how well it works it is wrong.

Bob Harper
09-17-2016, 05:13 PM
No listed liner visible. I guarantee you a level II inspection would reveal the need to reline this chimney.
No cleanout- subject to flue blockages
3" vent connector undersized. At >3ft vent rise, need 4" vent connector
vent connector not supported
vent connector inadequate vent rise
elbow cut down to attach directly to appliance flue gas outlet
No minimum 12" vent rise
not mfrs. draft hood
vent connector connection to chimney improperly executed. You can have smaller appliance's connector enter the flue above the larger or manifold them together then enter the common vent but not side by side.
If those vent connectors are cemented into the thimble they must be stainless steel
As to the draft hood issue: This 'could' be acceptable if the appliance mfr. doesn't have a problem with it and the AHJ signed off. Contrary to public opinion, you do Not HAVE to use the OEM draft hood IF, you use an 'approved' alternative. For instance, ASHRAE does not have a problem with replacing a draft hood with a bullhead tee with a double acting barometric damper so you can attach a spill switch to a thermocouple interrupter. I do this repair all the time and the AHJ's love it. That's what I'd do in this case:
Install a properly sized listed liner that enters as high up the wall as possible while still meeting clearance to combustibles. With the liner protruding into the CAZ 2-4 inches, transition to a galvanized steel manifold using a wye with a 4" snout to the WH. Three screws min. per joint, no seams between 5-7 O'clock on horizontal runs (less than 45° from vertical), supports every 4 ft. and at offsets, then the above modification.

Plumbers should figure the highest breaching possible, work their way back from there observing proper pitch down with adequate vent rise then that will tell you what height WH you can install.

Geoffery Corlett
09-18-2016, 10:43 AM
Originally Posted by Jerry Peck View Post
Nope.

Saying that something might be wrong infers that AT LEAST "something" might be wrong, that, potentially, "everything" could be wrong, and that, "potentially" something "might" not be wrong, but that is not the inference, that is a left over possibility ... not an inference. Not to be too nit-picky, but YOU imply, I infer! 🎓