Rusted terminals

Question is do you note in your report and recommend repair if there are rusted terminals in either HVAC, distribution or disconnect panels? What do you say?

Subjective call.
Couple of things to consider:

If the only corrosion that you see is some superficial rust, that may be OK, especially in an external panel.

If you have a thermal camera, and the those terminals are abnormally hot under load, it’s a red flag.
And, if the insulation on the wire leading to those terminals is discolored or warped (another indicator of poor contact), that too is a bad sign. What I see on the photo is OK though.

Also, look at where the copper meets the terminal. If you see excessive copper corrosion (green and white powder), that’s yet another “strike”

But, for superficial rust only, it’s not worth mentioning.

Another note: I know that wasn’t a part of your question, but I see some serious double-lugging there. Four pairs of wires attached to the terminals above those breakers.
That does not smell right at all.
Those Square D’s double-poles are NOT rated for two conductors per terminal.
And, if they doubled those conductors for increased ampacity (I’m betting a dollar on that too), that’s also wrong. You can’t use parallel conductors for increased ampacity at anywhere near that small of a wire size.
Call it out.


If those multiple conductors under one lug are factory connections as part of the equipment then they’re outside of the purview of the NEC.

90.7- The important parts to consider.

It is the intent of this Code that factory-installed internal wiring or the construction of equipment need not be inspected at the time of installation of the equipment, except to detect alterations or damage, if the equipment has been listed by a qualified electrical testing laboratory that is recognized as having the facilities described in the preced ing paragraph and that requires suitability for installation in accordance with this Code.

As Robert said…in terms of the factory component of the question…don’t dig too far into the weeds.

HVAC equipment comes with multiple conductors under one lug all the time and are apparently listed that way. As already stated this is outside the NEC.

I thought that was clear many posts ago.

Why go looking for trouble is my opinion.

I am curious as to why those who list these products allow the multiple conductors under lugs as pictured.

I will tell you this:

Having been a test engineer for one of the NRTLs, things do get missed and then there is the issue with accepted practice in industry. :wink:

Are you saying the testing methods are lax and you have no faith in the results or just saying that you do not like something that they have tested and found acceptable?