18 Inch Stands and Gas Water Heater Installation

[hausdok]

18 Inch Stands and Gas Water Heater Installation

The 2002 edition of the National Fuel Gas Code has been changed to reflect the new flammable vapor ignition resistant (FVIR) product. The FVIR product is a new American National Standards Institute (ANSI) testing standard that will prevent a water heater from igniting flammable vapors outside the combustion chamber. The new ANSI standard Z21.10.1-2001 will go into effect July 1, 2003. All 30, 40 and 50 gallon conventional vent gas-fired water heaters, both propane and natural gas, will have to meet the FVIR standard. PowerVent models and all remaining residential gas products such as 75 and 100 gallons and direct vent models will follow.The 2002 National Fuel Gas Code reads as follows:

• 8.1.10 Installation in residential garages

8.1.10.1 Gas utilization equipment in residential garages and in adjacent spaces

that open to the garage and are not part of the living space of a dwelling unit shall be installed so that all burners and burner ignition devices are located not less than 18 in. (460mm) above the floor unless listed as flammable vapor ignition resistant.

The 2003 International Fuel Gas Code has also been changed to reflect the exception:

• 305.3 Elevation of Ignition Source:

• Exception: Elevation of ignition sources are not required for appliances that are listed as flammable vapor resistant and for installation without elevation.

Do you have to put an FVIR compliant water heater on an 18-inch stand? The answer to the question will depend on the local, city, country or state codes that govern the installation of gas water heaters where you live. IF the local codes advise you to put the gas water heater on an 18inch stand, then you must do so.

You should comply with the local codes and governing agencies until their codes relating

to 18-inch stands have changed. If in doubt, please contact your local plumbing inspector.

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[Gordon]

Does the gas code mention any type of partition that is at least 18" tall, to be installed in front of any existing or new water tank, or older boiler systems?

Gordon

[hausdok]

Hi Gordon,

Don't think so. If it's wrong, it's wrong. An 18inch partition isn't going to change that fact. If it is accessed from the garage and shares air with the garage it is "in" the garage and needs to be raised.

ONE TEAM - ONE FIGHT!!!

Mike

[Paul MacLean]

Down here all new water heaters are FVIR types and they still install them 18" above the garage floor. It's such a simple thing to put them on a stand, everyone has continued to do so. I like it.

[hausdok]

Yeah,

Sort of the belt and suspenders method.

I think it's a good idea. With the old style water heater, even if it was more than 18 inches off the floor you could still end up with an explosion in a tight garage if you had a car with a serious gas leak.

The FVIR heaters are designed to contain the "combustion" but the results of containing the combustion essentially ruins the water heater and it needs to be replaced. So, the argument is, "So what, at least the house didn't burn down?" True, but if it's on the stand it's far less likely to be exposed to fumes than if it's on the floor, so there's even less of a chance of even that happening. This is sort of Peckian logic, I know, but it works for me.

I don't write them when I see FVIR water heaters on the floor, but I certainly don't criticize the fellow who wants to continue to mount them on stands.

ONE TEAM - ONE FIGHT!!!

Mike

[Brian G]

Originally posted by Paul Maclean

It's such a simple thing to put them on a stand, everyone has continued to do so. I like it.

---

Originally posted by hausdok

Sort of the belt and suspenders method.

I think it's a good idea.

---

I agree with you fellas. The best safety is in layers, as in more than one.

Brian G.

Raise Em' Up

[MichInspector]

Originally posted by hausdok

Yeah,

The FVIR heaters are designed to contain the "combustion" but the results of containing the combustion essentially ruins the water heater and it needs to be replaced.

This is not the case on all FVIR water heaters, though it is on Rheem/Ruud units I believe. The Bradford-White Defender series does not destroy the unit when protecting against flammable vapors. It has a resetable and replaceable thermal sensor.

Incidently Bradford-White still has the 18" clearance sticker on the Defender series, sort of a CYA I guess.

Todd