DIYbanter - Water Heater air gap, below T&P valve

"mm" wrote in message
...
Does there really have to be a full 6" gap betwen the bottom of the
T&P discharge pipe and the floor?

I don't see the purpose of it.

The instructions that came with the water heater say to leave a 6" air
gap between the temperature and pressure pipe and the floor drain.
The water heater that was first installed in the house was like that
too.

I have a pan under the WH and if the discharge pipe came to within an
inch or two of the pan, I think more of the water would go into the
pan when I lifted the T&P lever. And less on the floor.
Be aware that, if the T&P valve should ever be called on to do what it is
intended to do, what comes out of the pipe is a tremendous blast of boiling
water and steam. Whether it goes into the pan first or directly on the floor
would not matter much. The six inches is intended to ensure that the heater
be vented as rapidly and safely as possible, and also to minimize any
possibility that the water in the heater could ever be contaminated by drain
or ground water. I agree that it is nice to understand the reasons for code
requirements, but if you do not understand the reason that is all the more
reason to comply since there is obviously something you haven't thought of.
Codes are primarily for safety, after all.

Don Young