Corrosion on main lug

[Anna]

Hi all,

Seeking some advice here as I am purchasing a home where the inspection turned up a corrosion on the main lug. I've been speaking to a few electricians, one of which has stated that he believes it will not be possible to replace just the lug and that he will need to replace the whole panel. The panel itself is quite new, about 5 years old, and I am wondering if it is necessary to replace the whole panel or if there is a better way to do this. Furthermore, anybody have any ideas on how this one lug became corroded? I am also hoping to source the root of the corrosion to avoid any future issues.

Here is a photo of the issue at hand
https://ibb.co/128nkxw

Thanks in advance for your help.

Edited June 10, 2020 by Anna

[Marc]

1 hour ago, Anna said:

Hi all,

Seeking some advice here as I am purchasing a home where the inspection turned up a corrosion on the main lug. I've been speaking to a few electricians, one of which has stated that he believes it will not be possible to replace just the lug and that he will need to replace the whole panel. The panel itself is quite new, about 5 years old, and I am wondering if it is necessary to replace the whole panel or if there is a better way to do this. Furthermore, anybody have any ideas on how this one lug became corroded? I am also hoping to source the root of the corrosion to avoid any future issues.

Here is a photo of the issue at hand
https://ibb.co/128nkxw

Thanks in advance for your help.

Higher temperatures accelerates corrosion and I see at least two indications of overheating in that photo. I'd be suspicious of any sparky wanting to sell you a new panel when he can't give you a decent reason what went wrong with the current one.

 With just the one photo to go on, I'll wager the connections weren't good enough to prevent overheating. Decades of making lug connections in industrial settings well in excess of 500 amps has taught me that the lugs should be re-tightened after a few weeks. They tend to loosen for reasons I've never clearly understood.

I suspect the panel can be saved.  It just needs to be cleaned, the corroded lugs replaced, excessively corroded copper replaced, and every last connection checked.

Edited June 10, 2020 by Marc

[Anna]

24 minutes ago, Marc said:

Higher temperatures accelerates corrosion and I see at least two indications of overheating in that photo. I'd be suspicious of any sparky wanting to sell you a new panel when he can't give you a decent reason what went wrong with the current one.

 With just the one photo to go on, I'll wager the connections weren't good enough to prevent overheating. Decades of making lug connections in industrial settings well in excess of 500 amps has taught me that the lugs should be re-tightened after a few weeks. They tend to loosen for reasons I've never clearly understood.

I suspect the panel can be saved.  It just needs to be cleaned, the corroded lugs replaced, excessively corroded copper replaced, and every last connection checked.

Thanks, Marc. That's incredibly helpful. The electrician's response to why he can't save the panel is below - does this make any sense to you or does it sound like he's just trying to sell me a panel?

"Many times we try to remove corroded lugs either the buss bar is damaged or the lug gets stripped. Corrosion causes many problems with removal of screws and nuts. If we can not remove it or damaged in process there will be no option but to replace the panel. We take this on a case by case, sometimes we get lucky but most of the time, it is so bad we can not remove the lug."

[Marc]

I can relate to what the electrician is saying but if I were he, I'd be trying hard to make this one of those panels that I was able to save. I'd be aggressive, on account of it being only 5 years old.

I don't need to tell you, that as a contractor who will profit if he gets to change your panel, that electrician is conflicted in being objective in his assessment of your panel.

One more thing, aluminum doesn't have to be corroded to strip.  I've had too many, some brand new, strip on me, to the point where I hated them.

Edited June 10, 2020 by Marc

[Jim Katen]

I'll bet you a dollar that it'll be impossible to remove that lug cleanly.