Local electricians puzzled

[Stray Electron]

She built the house 20 years ago. Nothing else around the house is corroding so I think the drywall can be excluded. 

I don't think that's a valid conclusion, since the other drywall is similar drywall, not the same drywall.  IOW, there could be single panel that has a severe problem.  The timeframe of her building the house corresponds to the time that the defective drywall was in the market.  The reason I had asked you if the copper wires were blackened is because this would indicate the likely presence of hydrogen sulfide or similar sulfur compounds.  Some of those deposits look like sulfur but I definitely wouldn't recommend tasting them!  The possible sources of the hydrogen sulfide also include natural gas and rotting biomass.  The house wasn't built over a landfill, was it?  In any case, I think this is a serious issue and you/she probably needs to have those deposits analyzed ASAP, and probably should tear out the wall as well.  You also probably need to hire a contractor to test for H_2S, methane and maybe ammonia and formaldehyde.  Or you can start with an H₂S detector:

https://www.industrialsafetyproducts.com/msa-altair-hydrogen-sulfide-gas-monitor/?gclid=CjwKCAiA4KaRBhBdEiwAZi1zzvkvLiqIFcp4cgLKEXFDMoxSjoC8Y7Zg-TXeDfhPY8FVeE6HcmdstxoC9yUQAvD_BwE

Also, FWIW, that oil coming out of those cables doesn't look like the typical plasticizer issue to me, although I'm no expert.  I wouldn't expect it from NM-B from that era.  And that means you should really investigate that as well.

   I've never seen white powder like that in a breaker box and I use the same breakers (built here in 1979 and an outbuilding in about 2006).  Its very strange that the inside surface of box itself is clean! I have no idea what would cause the powder on the plastic breakers but not on the metal surfaces of the box. But I see that the electrical contacts on the RH side also have it!

  Corrosive drywall has been a HUGE problem in my area!  In the 1990s they built tens of thousands of houses here using drywall from China that contained sulfuric acid and the fumes attacked the copper water pipes and ate holes in them. My mother and my MIL both had to have their houses completely replumbed in less than ten years.  I'll also seen rolls of brand new never used wiring from China that contained some kind of impurities that caused the copper to be completely eaten away inside of the insulation. Not just near the ends but the entire 500 foot length!  I suspect that your brown goo might be due to some kind of chemical impurity in the insulation. The Chinese are notorious for impurities in just about all of their products. It's how they dispose of the majority of their toxic waste. Just about all of the building products that were contaminated here were bought from the absolutely cheapest source available, Home Depot.

   The first thing that I would do would be to pull the covers from the AC outlets, switches, etc and see if that end(s) of the wires have the goo problem.  If any of them do, then IMO, that entire house should be rewired and everything replaced and I would make DAMMED sure that none of the material came from China.

  PS   I think I would also contact Square-D and tell them about the problem and see what they say.  I'm sort of wondering if your breakers really were made by Square-D or if they might be counterfeit. You never know where a contractor or sub-contractor might have bought their parts and if they were legit or not.

[nfmax]

Any seismic activity in the area recently? That may have released some trapped H2S - though how it could get to one particular panel I have no clear idea.

[cdev]

This is a web site that explores home inspection issues.. weird ones like this should be checked out. Whatever is causing it it might be toxic or dangerous!

https://inspectapedia.com/

[james_s]

I've had wire do that too, whatever it is heavily corrodes the wire and makes it almost impossible to solder. This is truly bizarre though, I've never seen anything like it. I think chemical analysis is very worthwhile. I would also certainly not taste it, some chemicals including metal salts can be highly toxic even in small amounts.

[coppercone2]

leave some metal samples around to see how they react on different surfaces

Maybe the electricians truck was left open near someone cleaning concrete and the stuff for the job got exposed. Some tire cleaners and wheel well cleaners are aggressive also, and might do some damage to goods inside of a truck if cleaned with pressure washer. Not hard to imagine that as the weather is warming up someone decided to hose off the truck from a winters worth of road salt and then give it a good going over with everything in autozone so people don't think its a mine cart.

[robert.rozee]

brilliant thread, i haven't laughed so much in years!   

my money is on you having a RATS NEST in the wall cavity above the switchboard, and that the white and yellow power/corrosion is in fact the residue from rat urine. being the northern hemisphere, you'll be close to heading into spring, and the little vermin will be waking up from their winter nap and becoming active again.

they will have chosen the location above the switchboard to hunker down because of all the vertical wiring, which creates a slightly warmer area above it at ceiling height (current carrying wiring gets warm, warm air rises).

now you could tear open the 'drywall', but you might not like what you find! perhaps call in pest control instead.


cheers from new zealand...

[Haenk]

a RATS NEST

I had that idea as well (as we might have a marten somewhere in the roofing, i needed to check for symptoms...) - but urine will have a very strong smell, that certainly won't go unnoticed.

Also I find it strange to see some traces running down from the screwholes of the covers.

I guess it's really best to open the wall.

[Niklas]

The yellowish substance might be something with sulphur. Any smell of rotten eggs or fart?
Except for oil burner, rubber industry or volcanic activity, any Chinese drywall or leaks of gas from fracking?

[antenna]

Update:

The goo can be ignored. An inch up the wire is dry.  When the wires were pushed through the conduit, a lubricant specifically for making that easier was used. It would seem that pushing the wires through the conduit made it collect on the ends. I can only imagine that the moisture and bacteria darkened it over time and that it was originally clear.

As for the white powder, definitely a chloride salt. When I looked for my pH indicator solution, I saw a bottle of OTO pool chlorine indicator and had an idea. I took one of those tiny vaseline lip balm containers and glued in two small MMO anodes. A tiny amount of the corrosion (less than a tenth of a gram) was scraped into the container and a tablespoon distilled water added. 15 seconds with a 9v battery to the electrodes made the chlorine content evident by smell alone, but the OTO confirmed it. 100% for sure a chloride salt. And with the after burn from tasting it for saltiness, I am now confident that this chloride is a road salt mixture as magnesium and calcium chlorides burn like that. The corrosion did cause a slightly acidic response from universal indicator solution, but I am guessing that when the salt attacks the aluminum bus bars, the aluminum chloride formed hydrolyzes in the moist environment to aluminum oxide liberating small amounts of HCl gas as a byproduct (which may also have had a darkening effect on the lube used in the conduit).

The electrician is expected to return in the next week sometime and the garage humidity is now well under control. I suggested that they ask the electrician to apply dielectric grease to the bus and terminals after he cleans out the crud. She is also now planning to build a closet around the panels to keep them a bit warmer and isolated from the garage environment.  They also plan to look into resealing the cement floor as the coating is wore off on about 30% of it. The floor is a big saltwater sponge right now.

With all this, I think we have it narrowed down to a combination of the floor holding salt water, the floor heat malfunctioning to full heat, and the panel suffering from excessive galvanic corrosion with a side reaction where the aluminum produces trace HCl gas in an enclosed space. And I also believe that the migration of this salt is due to efflorescence.

No sulfur smell, and I am very sensitive to sulfur compounds so I would have certainly noticed that.  Thanks to everyone!!! If I have any further updates, I'll surely post them.

[coppercone2]

Well if you insulate the wires they will be more likely to overload.. if you start doing things like adding electric cars to the household it might be a problem.

The gel you speak of is sold in the hardware store in a 'sauce' bottle, for pulling wires through conduit. I worked a bit with conduit recently and if you store the conduits outside for a long time, insects *mud daubers?* like to fill up the pipe, we had to make a special tool to drill through it out of a long rebar. I recommend flushing them out before installation if stored outside too, using a brush and soap, then drying them. You want that interior surface clean so the heat gets out easier, if you have a layer of mud its like a insulating coating. If you look at a circuit panel with a thermal imager its usually clear that the wire gets warmer near the inlet of the conduit pipe.

But the risk of corrosion to junctions and breakers is also grievous, so I think its a good call, so long its specced out properly.

If you use the conduit gel, I recommend getting a cleaning wipe (i.e. the 'heavy duty' cleaning wipes from hardware store, that are scrubby cloth soaked in some kind of detergent) to clean the wires after they are pulled through the conduit. It's nice not to have dust and shit cake up the wires.. .so that's a little bit of lazyness on the electricians part.

[cdev]

Animals often decide to nest where there is a handy space heater. They like warmth.

Thanks to signage and its energy usage we have feral parakeets in Connecticut. (otherwise too cold for them) An opossum got into the attic of an apartment I had several years ago and decided to nest right about the lamp fixture in the middle of my bedroom ceiling. After weeks of hearing noises there I decided to remove it and take a look. I'll never forget what I found, a very cute opossum face just a few inches from my own, we both must have had that expression that said "what are you doing in my home!"

I'm sure the warmth was why he located himself there!

[Vtile]

Plastic decay (to acids and oxidicers) was my initial quess.

Mystery it is, but looking those images again, there is stains of dripping liquid inside and outside of the cabinets. The rats nest on top of boxes behind the wall could indeed be it.