Propane copper pipe corrosion

[GMike A]

Pulling out my carpet exposed about an eight inch section of copper pipe that is pretty corroded. This is located in the closet right at the entry point. Not sure if this will impact over time and eat the pipe or form a protective layer ala black pipe rust. It would be a PITA to change it but since the unit is gutted, now would be the time if it is necessary.

Any owners who are in the refrigeration or heating industry that could shed some light on what to do would be greatly appreciated.
thanks

[mary and bob]

You can try cleaning off the corrosion and see if the copper is pitted. If it is I would replace it. After cleaning it, pressurize the line and check for leaks with soapy water, liquid dish soap is good. There was a recent discussion about whether to use black iron pipe or copper on propane lines. If you have a flaring tool you could just replace that corroded section. DO NOT use the compression type fittings.

[Dennis Clinton]

That, my friend is the patina copper gets from being exposed to moisture. First thing, find out where the moisture is coming from. Then check to see if it has intruded into the actual pipe itself. Most likely, clean it off, remove the moisture intrusion, and your problem will be solved.

[Brian B-P]

The clean-and-inspect approach makes sense, but I personally wouldn't bother; I would just replace it, and do it right this time.

The two large grey lines arcing across the lower left corner of the photo are presumably water lines. Some points to ponder in a better installation: Why would a propane line be cable-tied to a water line? Does the propane tubing get mechanically stressed each time the water pump starts or stops and the water line shakes? Is the propane tubing getting wet each time cold water flows and condensation forms on the water line? Is the propane tubing sitting in a pool of water, as suggested by the copper corrosion products on surrounding surfaces?

[Thomas G.]

Those blue electric pinch-on connectors catch my eye. They are notoriously unreliable, especially in a area where corrosion is a problem. Just a heads up.

[cpaharley2008]

It looks like it was inside that piece of material which held moisture, it is patina which copper obtains with aging, not rusted, just clean it up and find the leak.
Nev-r-Dull will work on it.

[GMike A]

Agree Tom. There must have been two dozen of them in there and I stripped them all out except what you see now and that's right at the INPUT from the 7 pin, They cut the nice 12 gauge wire and added scotch locks right there and went to 14- could not believe it!!! And then down stream it goes back into 12 again.
I will have a nice bus line going from a fused box to all lights and accessories. Heavy gauge wire the old fashion way.

[Carol H]

Mike, I am with Jim sure looks by what looks to be signs of floor staining and the black spots on the wall covering etc that water may have been getting in from higher up?

[Thomas G.]

Originally Posted by GMike A

Agree Tom. There must have been two dozen of them in there and I stripped them all out except what you see now and that's right at the INPUT from the 7 pin, They cut the nice 12 gauge wire and added scotch locks right there and went to 14- could not believe it!!! And then down stream it goes back into 12 again.
I will have a nice bus line going from a fused box to all lights and accessories. Heavy gauge wire the old fashion way.

[Eddie Longest]

Mike
Do yourself a favor, order yourself a junction box from E trailer.
Eddie
Trailer Wiring Junction Box Spectro Accessories and Parts 38656

[Jared J]

Originally Posted by Thomas G.

Those blue electric pinch-on connectors catch my eye. They are notoriously unreliable, especially in a area where corrosion is a problem. Just a heads up.

The guy that designed scotch-locks should be flogged every time somebody has a trailer wiring problem. I'm almost done getting rid of them in my camper, and I've had to cut out about 12" of wire on either side to find shiny copper again, and splice a piece in with crimps and marine heatshrink.

[Francesca Knowles]

Interesting that the corrosion is limited to that section of copper that's in contact with the carpet. My guess is moisture wicking, could be from anyplace.



I'm with the don't-worry-about-it-if-there's-no pitting crowd. Do be sure to get rid of the carpet that's touching the pipe, and here's some advice from a hypercareful gas user:

Once it's all sorted out, a simple pressure test of the whole propane system can be done by any gas/RV place. I have mine tested once a year at a cost of about twenty-five dollars.

Francesca

[Jared J]

Originally Posted by Francesca Knowles

Interesting that the corrosion is limited to that section of copper that's in contact with the carpet. My guess is moisture wicking, could be from anyplace.



I'm with the don't-worry-about-it-if-there's-no pitting crowd. Do be sure to get rid of the carpet that's touching the pipe, and here's some advice from a hypercareful gas user:

Once it's all sorted out, a simple pressure test of the whole propane system can be done by any gas/RV place. I have mine tested once a year at a cost of about twenty-five dollars.

Francesca

Hijack, but can they test for CO from a cracked furnace manifold? I'm going to put a monitor in my camper, but I would like to have that checked anyway.

[Francesca Knowles]

Don't know if there's such a test...but if your manifold is cracked you probably want to weld/seal it up somehow. CO isn't a big hazard with propane, but certainly that manifold crack may interfere with the operation of the furnace.

Francesca

[Jared J]

It's not cracked that I know of, I just want to check. Supposedly, this furnace has never been turned on in 28 years, except possibly for the first few years.

[mszabo]

The brass fitting the copper line is attached to, is causing your problem.
You have discerning types of metals. The chemical reaction between the two, is the green buildup you are seeing.
You may need to look at it again in another 28 years.

[Francesca Knowles]

Originally Posted by Jared J

It's not cracked that I know of, I just want to check. Supposedly, this furnace has never been turned on in 28 years, except possibly for the first few years.

Sorry- guess I misread your post. If there aren't any visible cracks I wouldn't worry about the manifold being "cracked".

Especially since you think the furnace hasn't been used in so long, I definitely recommend a complete gas system pressure test once you've got all your new appliances installed. And do remember in your remodeling that all propane joints must be accessible for inspection for exactly this reason: if the test detects any leakage, joints are the most likely place one will find the source.

Francesca

[GMike A]

Thanks everyone. I like the distribution box Tom. May get several. I intend on using the mini-fuse with LED indicators, so I will have a fuse panel as well. I am going to take a scrubbie pad and wipe across the corrosion til I get back down to bare copper and then look to see if there is any pitting. The whole camper is gutted so not opposed to replacing it but didn't want to if not needed. Anything suspect and I will replace. Will have to check and see if there are any poly substitutes(?) or continue to use copper. I had an explosive gas and CO detector in my old camper and well worth the $50 bucks. Lost two dear friends 3 years ago when she forgot to turn off the car in the garage. Never woke up. Anyway a bit off subject but germane to gas safety inside the camper.

[GMike A]

Originally Posted by mszabo

The brass fitting the copper line is attached to, is causing your problem.
You have discerning types of metals. The chemical reaction between the two, is the green buildup you are seeing.
You may need to look at it again in another 28 years.

Thanks Mike on the metal reaction. Missed the reply from you as I scrolled down. Makes sense as lots of copper pipe gets wet but normally dont necessarily see sulphates like that. Good catch.

[mmeyer]

Originally Posted by GMike A

Thanks Mike on the metal reaction. Missed the reply from you as I scrolled down. Makes sense as lots of copper pipe gets wet but normally dont necessarily see sulphates like that. Good catch.

Doubt if it is the Brass causing the problem. Copper and brass only differ about .05V on the Galvanic series which is why all copper tubing uses brass fittings to keep corrosion down. I suspect the culprit is the blue scotch connector between the grey tubing. it appears that its metal crimp connector is on the bottom which could come in contact with judging from the color of the flake board wet conditions. add 12-14V and you can get a pipe of different color, add 120V and things could get interesting. since the corrosion only appears to be where it is in contact with the carper and the brass nut on the tubing is also in that area but the brass fitting is not it is likely the effects of stray current. Of course the fitting could have been changed out by the PO just to befuddle us.
Blue color can also indicate copper carbonate and several other copper salts some soluble and some not so much