"engineman" wrote in message
...
I have a gas line running to my outdoor hot tub water heater. When I
first installed it 8 years ago I used black iron pipe because i heard
that it was required.
Lately I've noticed that it is heavily rusted where it is lying on the
concrete.
Can I replace it with galvanized?


The question is, what are the codes in your area?
In my area we use International Mechanical Code and it does allow the use of
galvanized pipe for natural gas or propane. We can also run copper for
natural gas. Your codes may differ.
IIRC, according to IMC, black iron pipe less than 6 inches from the ground
has to be treated as underground pipe, and properly coated. If you get the
pipe over 6 inches off the ground painting is adequate. Below six inches the
coatings need to be for underground pipe, and painting does not meet the
requirement!.
Again, your codes may be different!
Now if it were my pipe, I would clean it well and paint it, and keep an eye
on it. If it is pitted badly, I would replace it with galvanized, and paint
any exposed threads.
Greg