Originally Posted by Redwood
The stand requirement depends on where it is being installed. But under many code now it is being dropped even when installed in a garage...
FVIR eliminated the need to raise the water heater off the floor to get above flammable vapors. Check your local code.
I do not think they should drop the requirement of a stand in a garage just because of the FVIR heaters. Yes FVIR is supposed to prevent the flame inside the heater from flashing outside the heater, and safely burn off the flammable vapors within the water heater. There is a few things that is flawed in allowing the FVIR heaters to be floor level in a garage.
- Rheem and a a couple others have a glass vile that breaks when the heater starts to burn of the flammable vapors. Once it is broke the heater is useless
- A.O. Smith and State have the fresh air intake on the very bottom of the water heater, most garage I been in are not the cleanest, so these heaters will act like a vacuum cleaner sucking all the dirt in though the FVIR screen and clogging it,again making the heater useless
- Due to the above mentioned issues I have seen people open the sealed combustion chamber and or busting out the sight glass to allow air to enter so the heater will operate, but bypassing the FVIR so now the flame can flash outside the water heater
Thats just the tip of iceburg to say. When I replace water heaters in a garage I still keep the stand in place.