corroded gas line

Paul S_3

this is a first for me. Have any of you seen a corroded gas line this bad. its only 6 years old. its located in an outside bar near an inground pool. i got called to this home because the pool heater wasnt working. in the photo below youll see my monometer reading of 5.5" w.c. ....that pipe goes into the ground not wrapped to the pool heater about 10 feet away. i get about 1" w.c at the pool heater....so clearly the pipe in the ground is compromised. i know underground gas piping should be wrapped with millwrap. but why is the above ground piping so bad? im replacing everything outside should all the piping be wrapped? what would you guys do? This is nyc so i cannot use that csst pipe.Also do you think scrapping the pool heater all together would be a good idea and use there hot water boiler.Boiler is 167K very oversized. ive heard of people using a water to water heat exchanger and a tekmar setpoint controller. any advice would be great guys. thanks (pool size is 24' by 10'.....ranges from 6' to 3' in depth)

ChrisJ

Holy crap.
I've got a black iron run out to my Weber grill under our back deck and I only painted the fittings when I ran it in 2012. It still looks like the day I did it.

Are they storing chlorine under there?

Paul S_3

no ...nothing is stored under there....just really damp

Zman

I think the problem is being caused by the pool chemicals. It only takes an environment with dampness cause by a slight leak from the pool (past or present) and you will see the very rapid corrosion you are seeing.
I worked on a hot tub vault with similar problems where 1/4" steel was completely corroded.
In our case we replaced the steel with stainless steel and ventilated the space.
Not sure what the best fix is in your case, I do think the pool chemicals are the issue.

Tim McElwain

A combination of probably pool chemicals and corrosion due to electrolysis caused by failure to protect the gas line. It should be replaced with plastic if your local AHJ will allow it.

All gas lines that are steel and buried should have corrosion protection especially with certain types of soil.

There is CSST that can be buried. I would contact the local gas company engineering department for their input and advice as they will know what the code is.

You could also sleeve steel pipe inside pvc to protect it just make sure you follow NFPA on the proper way to do that.

Gordy

Chlorine baby. Ask me how I know.

lchmb

on a good note his usage will go down when repaired...

hot_rod

It looks like more than just humidity or damp conditions caused that, seem like some chemicals were at play.

Here is an ell from a boiler gas line that had some flue condensate dripping on it. Thanks to Paul Rohrs for the pic.

EBEBRATT-Ed

What about plastic coated black pipe and wrap the joints