Vent pipe, TPR installation & Vertical clearance

[Patrick Knight]

Vent pipe: There is no UL label, and my best guess is that this is single wall. The clearance from roof deck is 0-1" and needs to be addressed and the vertical clearance is possibly an issue. I believe the gray area is soot. Any thoughts? How would you suggest to word this?

TPR: From what I understand about TPR's this is improper installation since the piping extends vertically and TPR is in a "T." I believe it should be installed in the side or flush with the top of the WH so it is a downward slope. There is no pan and the end of the piping is not visible.

I know I need to make comments about having a licensed plumber make reparations to the unit. Included: Install drain pan, relocate TPR, replace single wall vent with B vent, install insurance ring...and I'm listening for other suggestions...

Thanks,
PK

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[Jerry Peck]

Vent pipe: There is no UL label, and my best guess is that this is single wall.

Needs 6" clearance.

TPR: From what I understand about TPR's this is improper installation since the piping extends vertically and TPR is in a "T." I believe it should be installed in the side or flush with the top of the WH so it is a downward slope. There is no pan and the end of the piping is not visible.

*IF* that T&P relief valve is the extra long extension type, it *may* be okay, but even then it *may not* be okay. And that is typically only allowed if there is no T&P opening in the tank, and I am not aware of a water heater made in the last 50 years without a T&P opening, and many have two openings, one in the top and one through the side.

[Stuart Brooks]

Needs 6" clearance.



*IF* that T&P relief valve is the extra long extension type, it *may* be okay, but even then it *may not* be okay. And that is typically only allowed if there is no T&P opening in the tank, and I am not aware of a water heater made in the last 50 years without a T&P opening, and many have two openings, one in the top and one through the side.

Yep. The appearance looks like a DIY job where they just made it match an older installation. It is a very good possibility that "grey" on the ceiling is discoloration from continued heating of the wood. Its flash point can be reduced from overheating over time

[Widdershins Saunders]

Vent pipe: There is no UL label, and my best guess is that this is single wall. The clearance from roof deck is 0-1" and needs to be addressed and the vertical clearance is possibly an issue. I believe the gray area is soot. Any thoughts? How would you suggest to word this?

TPR: From what I understand about TPR's this is improper installation since the piping extends vertically and TPR is in a "T." I believe it should be installed in the side or flush with the top of the WH so it is a downward slope. There is no pan and the end of the piping is not visible.

I know I need to make comments about having a licensed plumber make reparations to the unit. Included: Install drain pan, relocate TPR, replace single wall vent with B vent, install insurance ring...and I'm listening for other suggestions...

Thanks,
PK

As Jerry pointed out, the TPR installation might be OK if the valve has a long probe (the probe must be immersed in order to operate properly), but from looking at the photo's, I'd say there isn't enough clearance above it to install a TPR with a long probe -- Also, the installation must be done in such a way as to be able to remove and replace the TPR without removing the tank.

Also worrisome about this installation is the direct connection of copper to the steel opening of the tank -- I cannot tell from the photos if they threaded a copper male adapter directly into the top of the tank or if they threaded a copper female adapter onto the steel nipple, but it doesn't matter, neither is acceptable. Such an installation is a recipe for electrolysis.

I've had installations where the factory installed TPR orifice was on the side and wasn't accessible, usually because of side clearance issues -- So it isn't all that uncommon to install the TPR in the top of the tank -- The correct way to do this is to thread a brass tee onto the nipple and then thread a long probe TPR into the top of the tee.

Where is the tank installed? Is it in an attic above all of the plumbing fixtures?

If it is, it should have a vacuum relief valve installed to prevent the tank from siphoning.

[David OKeefe]

What I'm seeing is the TPR valve t-ed into the hot water line. I've never seen these two in the same line, always separate. Is this application OK?

[Rick Hill]

It is good the house was still there to inspect. It looks like the single wall pipe in contact with combustables has degraded the wood. In a very tight area combustion air may also be an issue.

[Brandon Whitmore]

I would pull up the installation instructions for this water heater. At least some of the ones I have read require a specified clearance between the top of a water heater and "alcove"

See page 9 of this document for an example: http://www.bradfordwhite.com/images/...-44219-00J.pdf

[H.G. Watson, Sr.]

Vent pipe: There is no UL label, and my best guess is that this is single wall. The clearance from roof deck is 0-1" and needs to be addressed and the vertical clearance is possibly an issue. I believe the gray area is soot. Any thoughts? How would you suggest to word this?

TPR: From what I understand about TPR's this is improper installation since the piping extends vertically and TPR is in a "T." I believe it should be installed in the side or flush with the top of the WH so it is a downward slope. There is no pan and the end of the piping is not visible.

I know I need to make comments about having a licensed plumber make reparations to the unit. Included: Install drain pan, relocate TPR, replace single wall vent with B vent, install insurance ring...and I'm listening for other suggestions...

Thanks,
PK

From the photos, and descriptions you offered and in response to your first question, how to word, well I would start with:

DANGER! (on Many levels!)

as in immediate threat to life or fire.

Fire, explosion, asphyxiation, injury or death.

The concerns at "WARNING" and "CAUTION" levels are somewhat moot at this point as there appears to be "DANGER ALERT" conditions already present and photographed, therefore IMMEDIATE ACTION IS NECESSARY!

In the meantime, it should be shut down, tagged out, and likely the property won't be occupiable without hot water and until the roof assembly is remediated, but still the occupants, in addition to the owner (if otherwise), the utility, and the authorties (building dept, and/or fire department) SHOULD BE NOTIFIED.






Next I would not classify or suspect as soot, but suspected pyrolysis, specifically looks carbonized!

The placement/location of the water heater is incorrect, as well as the venting, relief valve, and eveything else associated with this installation!

Above the top of the appliance itself for its entire circumfrence there is a required zone height of non-combustible clearance. This includes the area at the appliance flue termination (below the draft hood) behind it (as pictured) and above: insufficient clearance "zone" from combustibles and unencumbered or interferred "air space" 360 degrees for a column for draft hood (apparent sloping roof assembly) for the Cat. I (draft hood) water heater.

The draft hood, the appliance connector does not have sufficient clearance. The appliance connector is not the right size, has been modified (crimped or bent from backside to "form" it to 3" draft hood!!!)
There is SO MUCH WRONG.

Might help if you filled out your profile, told us what perspective we're addressing here - are you a student, HI, building inspector, home owner, contractor, home purchaser?

The connection/transition to the corroded/damaged larger "vent" is not correct and open! There is insufficient rise prior to transition. If had been relocated could/should have used properly sized, etc. b-vent from drafthood on up properly supported.

Reference to ROOF and apparent ATTIC installation, single wall vent gas appliance connectors should NEVER BE INSTALLED IN ATTICS.

I would expect copious spillage every time it operates and if piloted zero venting in between cycles.

This is a DANGEROUS installation on many levels; and should be taged out, occupants, utility, and authorities (building/ahj and fire officials) notified IMMEDIATELY.

Carbonized wood and engineered wood products do not maintain the qualities of non-pyrolyzed - i.e. can burst into flames at much lower temperatures, etc. Therefore remediation of the roof assembly is also required. Cannot properly vent - temperatures produced from Cat I gas fired, products of combustion, and improper combustion pose DANGER to life and property.

ANSI Z223.1 or NFPA 54 or National Fuel Gas Code or NFGC (all references to the same thing) are OFTEN (if not always) referenced in gas-fired storage type water heater manufacturer's instructions, and upon safety labels applied thereto. You can view NFPA 54 (aka NFGC aka ANSI Z223.1) at the National Fire Protection Association's web site in view only mode for free.

You may also find this article (although its an older one circa 1992-95 ish)on venting gas fired appliances helpful before you "dive" into NFPA 54's more recent addition: CATEGORY I VENT DESIGN

[H.G. Watson, Sr.]

I probably should have better referenced and mentioned barricade tape as well as lock-out in addition to tagging out, informing occupants and signage and safety alert symbols.

Please see the ANSI Z535 series, Z535.5 "Safety tags and barricade tapes" Z535.3 "Criteria for safety symbols", and Z353.6 "Collaterial materials", etc. See 2006 editions or later, especially Annex.

Following is attached (pdf file) of an article suggested by Michael Thomas in another topic discussion on, water heaters, (thanks, M.T.!) it is the work of Applied Safety and Ergonomics, Inc.

You may view on line with Adobe reader at this (clickable) direct link: http://www.appliedsafety.com/ansi_z535dot6_article.pdf

(The attached pdf file is a copyrighted 2006 Applied Safety and Ergonomics, Inc. publication, licensed under a Creative Commons Attribution-Non-Commercial-NoDerivs 2.5 License. You may only copy or distribute the attached document without alteration and for noncommercial purposes, and you must attribute the work to Applied Safety and Ergonomics, Inc.)

The equipment (water heater) and collateral materials have not been installed or maintained in keeping with the manufacturers' instructions, specifications, and present hazardous conditions DANGER to persons and property.

Hope that helps.

[David OKeefe]

Mr. Knight,

The clearance from combustibles for single wall is 18'' inside a building and 6'' on the exterior.

I have not heard of the 18" clearance before. 6' is what I have always used. Is this a Cal. State code?

[Jerry Peck]

The clearance from combustibles for single wall is 18" inside a building and 6" on the exterior.

Single wall is not allowed outside the building in uninsulated space anyway, neither is it allowed to run through an attic.

From the IRC: (bold and underlining are mine)
- G2427.7 (503.7) Single-wall metal pipe. Single-wall metal pipe vents shall comply with Sections G2427.7.1 through G2427.7.12.
- - G2427.7.1 (503.7.1) Construction. Single-wall metal pipe shall be constructed of galvanized sheet steel not less than 0.0304 inch (0.7 mm) thick, or other approved, noncombustible, corrosion-resistant material.
- - G2427.7.2 (503.7.2) Cold climate. Uninsulated single-wall metal pipe shall not be used outdoors for venting appliances in regions where the 99-percent winter design temperature is below 32ºF (0ºC).
- - G2427.7.3 (503.7.3) Termination. Single-wall metal pipe shall terminate at least 5 feet (1524 mm) in vertical height above the highest connected appliance draft hood outlet or flue collar. Single-wall metal pipe shall extend at least 2 feet (610 mm) above the highest point where it passes through a roof of a building and at least 2 feet (610 mm) higher than any portion of a building within a horizontal distance of 10 feet (3048 mm) (see Figure G2427.6.4). An approved cap or roof assembly shall be attached to the terminus of a single-wall metal pipe (see also Section G2427.7.8, Item 3).
- - G2427.7.4 (503.7.4) Limitations of use. Single-wall metal pipe shall be used only for runs directly from the space in which the appliance is located through the roof or exterior wall to the outdoor atmosphere.
- - G2427.7.5 (503.7.5) Roof penetrations. A pipe passing through a roof shall extend without interruption through the roof flashing, roof jack, or roof thimble. Where a single-wall metal pipe passes through a roof constructed of combustible material, a noncombustible, nonventilating thimble shall be used at the point of passage. The thimble shall extend at least 18 inches (457 mm) above and 6 inches (152 mm) below the roof with the annular space open at the bottom and closed only at the top. The thimble shall be sized in accordance with Section G2427.10.15.
- - G2427.7.6 (503.7.6) Installation. Single-wall metal pipe shall not originate in any unoccupied attic or concealed space and shall not pass through any attic, inside wall, concealed space, or floor. The installation of a single-wall metal pipe through an exterior combustible wall shall comply with Section G2427.10.15. Single-wall metal pipe used for venting an incinerator shall be exposed and readily examinable for its full length and shall have suitable clearances maintained.
- - G2427.7.7 (503.7.7) Clearances. Minimum clearances from single-wall metal pipe to combustible material shall be in accordance with Table G2427.7.7. The clearance from single-wall metal pipe to combustible material shall be permitted to be reduced where the combustible material is protected as specified for vent connectors in Table G2409.2.

Now, Table G2409.2 contains clearances for single wall from 6" to 9" to 18" to 36", which means that one would need to look in the table for the installation use, and, for that water heater, the clearance is 6".

[H.G. Watson, Sr.]

No, there isn't a 6" clearance, an 18" clearance, or any clearance its not allowed here.

G2427.7.6 (503.7.6) Installation. Single-wall metal pipe shall not originate in any unoccupied attic or concealed space

Not allowed, to originate (originates at the draft hood) in this unoccupied attic, period.

However its moot. It all must be shut down, NOW.

[Widdershins Saunders]

No, there isn't a 6" clearance, an 18" clearance, or any clearance its not allowed here.



Not allowed, to originate (originates at the draft hood) in this unoccupied attic, period.

However its moot. It all must be shut down, NOW.

I've seen a lot of similar installations (single wall, attic space and incorrect clearances) in Mississippi, Alabama and Louisiana over the past 5 years -- Mostly as a result of the reconstruction done after Hurricane Katrina.

I'm not saying it's right or that it should be allowed to stand, particularly this specific installation. OTOH, the majority of similar installations I saw in Gulfport and Mobile were signed off by the AHJ.

A Plumbing Inspector in Gulfport, Miss explained to me that they let a lot of things slide due to a shortage of materials and labor.

He was a nice guy -- I hope none of the sketchier things he let slide ever come back and bite him in the butt.

[Stuart Brooks]

[quote=Widdershins Saunders;157251 ... snipped ...
He was a nice guy -- I hope none of the sketchier things he let slide ever come back and bite him in the butt.[/quote]

Or cause the death of someone in the houses he passed.

[Jerry Peck]

Not allowed, to originate (originates at the draft hood) in this unoccupied attic, period.

That may not be originating in the attic (at least I did not see anything in the post about that being an "attic", and presuming that it is an "attic" may be correct, but it may also be incorrect. That MAY be allowed to originate at that water heater and go through that roof - just not as shown.

G2427.7.4 (503.7.4) Limitations of use. Single-wall metal pipe shall be used only for runs directly from the space in which the appliance is located through the roof or exterior wall to the outdoor atmosphere.

An example of what that 'could be': the water heater 'could be' in a space where there is no ceiling and the single wall vent runs directly up and out through the roof.

H. G. is probably correct in thinking that is an attic, but it might not be an attic ...