Copper Gas Lines

Alan (California Radiant) Forbes

This connector was on a 70 year old boiler and I was surprised that the debris didn't clog the gas valve. Does anyone know if it's the hydrogen sulfide component in natural gas that causes the build up?

mattmia2

i do know that the code usually says you can only use copper if the gas has under a certain sulfur content.

if it is 70 years old that could have been on town gas originally and that crud is condensate from that

Alan (California Radiant) Forbes

if it is 70 years old that could have been on town gas originally and that crud is condensate from that

It's in Oakland

ChrisJ

That's some really clean copper and brass for even being 20 years old.
I'm not buying 70.

mattmia2

I have seen it turn black in a couple years where it is damp and look like that where it is dry after 50 years.

JUGHNE

When we got NG here in the late 60's, KNE would not allow anything except black pipe.
They would use copper outside underground to NG yard lights...always on like those in New Orleans I noticed.
But the copper was internally tin lined to prevent the sulfides from doing that.

IDK about the cleanliness of the gas today, I see a lot of copper in the cities but we are still pipe and CSST systems.

I have noticed the same scale with LP on copper lines

Larry Weingarten

Hi, My understanding is that the mercaptan odorant is what causes this. Here's some research: https://www.copper.org/applications/fuelgas/pdf/south_cal_gas_final_report.pdf I think using a garden hose for gas is safer

Yours, Larry

kcopp

I have seen hundreds of 2# systems that were done in soft copper. It is the sulfur that causes the flaking. Over in the UK they use soldered copper and fittings to run gas pipe all the time. They dont have issues...not sure what the sulfur content is there.

Alan (California Radiant) Forbes

@ChrisJ: OK, maybe not 70 years old. How about 67?

The house was built in 1954 and the son of the original owner still lives there. He says it's the same boiler. The piping looks original too.

mattmia2

Where was this piece of copper at? That boiler is from 1954.

Bob Harper

Code allows 0.3 grains of hydrogen sulphide per 100 scf. If greater then can't use copper or galvy steel. The black flakes are copper sulphide. This is one of the reasons you still incorporate a sediment trap at the appliance by code. Find out from the utility the analysis of the gas.

ChrisJ

Alan (California Radiant) Forbes said:

@ChrisJ: OK, maybe not 70 years old. How about 67?

The house was built in 1954 and the son of the original owner still lives there. He says it's the same boiler. The piping looks original too.

67 sounds a lot more realistic to me.
Why didn't you just say that?

The house I grew up in had a Mueller Climatrol furnace from 1958 that was still running fine when my parents sold the house in 2006. It had the thermal couple changed in the early 80s and the gas valve changed in 2004.

Now, we laugh when people want something that's 20 years old fixed...................

mattmia2

That boiler is older than 67. That gas chain wouldn't have been legal after the change to total shutoff which I think was in the early 60's. It appears that boiler was originally installed with black iron to the gas valve, that copper is likely too small.

JDHW

@kcopp and @ Bob Harper

In the UK copper pipes for gas are the standard from the meter to all appliances in single family homes. In places like blocks of flats I think it is threaded steel pipe within the main building risers and then copper within the individual flats. I have recently taken out some 40 year old gas piping and there was no sign of internal corrosion or debris.

Composition for gas is nationally controlled - https://www.nationalgrid.com/uk/gas-transmission/data-and-operations/quality

Seems that the permitted levels of sulphur compound are much lower than in the US? Trying to translate the units makes me appreciate why we went metric :-)

Regards
John

mattmia2

The US generally does not control sulfur emissions as well as other countries.

EBEBRATT-Ed

@mattmia2

67 years old, not 1967

STEVEusaPA

Alan (California Radiant) Forbes said:

@ChrisJ: OK, maybe not 70 years old. How about 67?

The house was built in 1954 and the son of the original owner still lives there. He says it's the same boiler. The piping looks original too.

If only your son knew someone who could put in a modern, more efficient boiler...

PC7060

Re the age of the supply line; when did 2PSIG systems become prevalent? That when I started seeing copper supply lines.

Re @mattmia2 comment on copper pipe size. The configuration in the picture has a pressure regulator; am I correct in assuming that this is a 2PSI G system with the regulator reducing pressure to 5in WC?

mattmia2

No. It is just a ~6" wc system. The regulator is just for the burner in the boiler. Modern valves have the regulator and valve and safety valve all integrated in to one device. On these older systems the regulator and the valve were separate.

Alan (California Radiant) Forbes

If only your son knew someone who could put in a modern, more efficient boiler...

Why make trouble? The owner is my age and doesn't want to have problems when he gets older. We replaced all the zone valves, zv control, fill valve and installed all new ball valves, hose bibbs and purge assembly beacuse they were either missing or had problems. The boiler, on the other hand could go another 50 years.