The following are the general requirements for the installation of the garage gas water heater with respect to the height of the burner chamber above the floor surface. Depending on the model / type / age of your particular water heater and your jurisdiction, they may or may not apply; always check before installation.
If there is no manual explaining the installation requirements for your appliance, contact the manufacturer and ask for the installation instructions for your particular model (in most cases, you can get it online).
However, the rules listed below are extremely important. If they apply to your appliance, you may be putting your life in danger if you don’t follow them.
As a general requirement, you should not install a water heater anywhere gasoline, flammable vapors or liquids, and combustible materials are likely to be present. Such installation can cause an explosion or fire, but sometimes there may be no other options. If this is where you are right now, you must follow the rules.
1. How high should the WH rise from the garage floor?
The garage (detached or attached) is one of those non-preferable places for the installation of the water heater, but sometimes it is the only one.
The ignition source (pilot, electronic igniter, hot surface igniter, etc.) must be 18 “from the garage floor.
The same rule applies to WH that has been installed in a room that opens to the garage, such as a utility closet or laundry room. This applies even if the doors between the garage and the appliance room are watertight or close automatically.
2. The ignition source for the water heater must be 18 “above the floor in an area where flammable materials are stored.
If you are installing the WH in an area that is also dedicated to the storage of flammable materials or there is a potential for such materials to be stored there, place the appliance on a platform so that the ignition source is at least 18 “above the the surface of the floor platform is capable of supporting the weight of the filled WH.
The way it often works in our homes is that while we are looking for some storage space, we fill our utility room / closet with everything that doesn’t fit anywhere else. Things like paint chips, paint thinner, all kinds of cleaning chemicals, containers full of emergency gasoline, etc., are generally found here. Is this what your WH wardrobe looks like? Well, you are not alone.
In addition to accidental spillage, some of those plastic containers can simply melt while next to or on top of the water heater, spilling their contents and causing fumes to ignite under the WH and inside the burner chamber. based. Don’t push it to the side! Get it out of there!
Bad news: Most WHs manufactured before 2003 had an open combustion chamber and were not equipped with a safety device to prevent ignition of steam.
Good news:
- Beginning July 1, 2003, all 30-, 40-, and 50-gallon residential atmospheric venting (natural draft) water heaters must be equipped with a flammable vapor ignition resistant FVIR design.
- July 1, 2006 – Same requirement applied to 30-, 40-, and 50-gallon electric vented residential gas water heaters with less than 75,000 BTU input
- July 1, 2007 – WH conversion to FVIR design has been extended to all residential water heaters with inputs of 75,000 BTU or less, including Power Direct-Vent, Direct-Vent, Manufactured Homes, and higher gallon capacity models not covered in the first two phases.
3. It is not necessary to raise the gas water heater above the floor if the WH is resistant to ignition by flammable vapor FVIR.
Theoretically, this allows you to install the FVIR-equipped WH in all of the locations explained above, without the previously required 18 “lift. Newer water heaters have a sealed combustion chamber / burner and a push-button igniter mounted on the exterior Although they still draw combustion air from the surrounding area, the protections incorporated into this new design prevent gas or vapors ignited within the chamber from escaping into the room.
I said that “theoretically” you can bypass the 18 “elevation requirement for those critical locations and install a type WH FVIR directly to the floor in such environments (ie garage floor). However, WH manufacturers and some jurisdictions they can still recommend (or require) that even FVIR water heaters be installed 18 inches above the garage floor.
Always read the manual and call your local code enforcement division before installation; this could save you time and money.
4. Above-floor installation of the gas water heater
Requires a 3 “pedestal (concrete, etc.) to minimize moisture / corrosion infiltration.
5. Gas water heaters in the fuel floor
They can be installed directly / without elevation on a combustible floor (unless otherwise specified in your manual or in your local jurisdiction), except on carpet. If it must be installed on a carpet, a wood or metal panel must be placed under the WH, extending at least 3 “beyond its base in all directions.
6. Electric water heater in a garage.
Some jurisdictions may also require the electric WH to be raised above the garage floor. Due to the location of the lower heating element, it may be necessary to lift an electric WH 10 to 12 inches off the floor; Check first!
7. The water heater installed in the garage requires guards / bollards to prevent a car from entering it.
That should cover the basics of garage gas water heater installation and burner chamber height above the floor surface.
