Sticking your tongue out- a tongue of fire!


Now there are some people (speaking for a friend) who suggest that their spouse may have a tongue of fire. As to the Marvelous Meggy, even though she is a redhead, I would never assert that I have been burned, warmed perhaps but…

Moving right along. We performed a home inspection recently where a water heater stuck a tongue of fire out into the closet where it was located. In fact, the closet door had some scorch marks…scary.

Gas water heaters need air for their burner and if they cannot find enough air flowing the usual way then the flames will actually go looking for some. This is called flame rollout and it can burn your house down. Think of it as though we were talking about a man dying of thirst in a desert…when he gets thirsty enough his tongue will hang out seeking for even a drop. It is the same way with gas furnaces and water heaters.

So, Yesterday, we found that the water heater was installed in a very narrow closet with no source of fresh air. The building codes and the manufacturers actually have specified how much air is required for a water heater or gas furnace or both. The more flames then the more air is needed. The term for this kind of air is “combustion air” and the requirement is that there be 50 cubic feet (not square feet) per every 1000 btu required. So if you have a 40,000 BTU burner on your water heater then you need a pretty large room. Like a big laundry room.

So, if you have a furnace or water heater in a skinny closet then you need to provide some extra air to keep those flames where they belong. If your water heater closet is on an outside wall then you can cut a grill to the exterior but the typical solution is to provide air from the attic. This is a weird setup because it should be a vent pipe located at the ceiling of the closet and then another vent pipe that runs from the attic all the way down to within 12 inches of the floor. This will get the fresh air moving in your closet.

I have seen a variety of methods used to provide combustion air including louvered doors for the closet to the interior of the house or grills at the top and the bottom of doors. All kinds of variations on the theme however the key is that there are enough openings to provide enough free air. Remember that if there is a gas furnace using another 100,000 BTUs then you need a whole lot more combustion air. When in doubt call your plumber or heating and air guy and he will make the calculations…

Ned Dominick has been inspecting homes in Macon, Warner Robins, Bonaire, and all of Middle Georgia since 1978. He and his qualified inspectors have examined over 28,000 local homes. For more go to his website at or give him a call at 478-738-0893.


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