WARNING! HVAC fishy smell. WARNING!

[Dan Lane]

A couple of months ago, I posted a problem about my rear AC having a fishy smell.  I received suggestions to clean the fins, the filter, etc.  Did all of that and it fixed the problem temporarily.  I took the coach out this weekend and it smelled again.  My wife did a search on the internet for HVAC fishy smells and found a site that discussed the problem with house AC’s.  The site has 10 years of discussions, 31 pages, and they all said the same thing: the fishy smell is caused by an electrical problem.  When an electrical part overheats, it releases a chemical that smells like bad fish.  Since the smell was coming from the rear AC, I searched back in the bedroom and the smell was coming from the circuit breaker panel.  I touched it and it was very hot.  I turned off the generator and all of the breakers.

I had an electrician look at it today, and all of the breakers had heat damage, some were significantly melted.  The two breaker panels were also damaged and partially melted.  Had my wife not found this info on the internet, the coach would have at some point caught fire.  I will try to attach some photos that show the damage.

I had never heard of this problem and, from the articles she found, many electricians are also unaware of it.

[Larry H]

Thanks so much for posting.

[Dr4Film]

YIKES!

Would you surmise that this damage might have been caused from vibration, shaking and moving that is common when running the roads? If so, it supports the strong recommendations by this group to check all connections and circuit breakers yearly or more often.

[pulsarjab]

You may have a problem with loosing your neutral on 50 amp. Could be in a park where you plugged in or could be in your house wiring. I would check the inverter and the transfer switch for loose connections. I had a loose neutral in the transfer switch which took out the microwave and both TVs, and the inverter/charger. I was fortunate to have the computer equipment plugged in to surge protector that saved the computer. I now have a Progressive surge unit installed.

[Moonwink]

What is the brand of those breakers?  Have you researched to see if there's a recall on them?  They certainly should have tripped long before getting that hot. 

[trailmug]

I would be interested to know if the breakers are makes/models that are listed for the load center. A lot of stab-on breakers will "fit" without being intended for a use with a particular panel, and improper application is fairly common. I expect the fishy smell is the ABS out-gassing.

The one I can read appears to be a TB series.

Edited September 9, 2020 by trailmug

[Ivan K]

We had a 100 amp breaker melting up in our house main box feeding the shop few years after construction completion and inspection. It did not trip and I don't think it was overloaded because I have a lesser breaker in the shop panel and never tripped either. To me, the smell felt like a dead animal and for a while I suspected that something died inside the wall until I finally found it. It was a dual breaker but the only one that failed from many, you seem to have more of them failed the same way at the same time and that's weird. Maybe heat transfer through the mounting rail?

[quick_tox]

Square D breakers.  very cheap and readily available at HD.  Take one with you to make sure you get the right type. Is the aluminum bus damaged?  the whole back panel can be replaced cheaply.  I've never heard burnt insulation described as fishy odor.

[Dan Lane]

They are Square D and so is the panel.  I called a local dealer to find out if I could replace just the terminal blocks and he said I had to replace the panel and gave the part number to me, said he would order it for me.  Went the Monaco site, put in the part number and ordered for $50 less than what the dealer wanted.  I should have it next week.  BTW, the part number is 10106231 for the one I have.

[trailmug]

2 hours ago, Dan Lane said:

They are Square D and so is the panel.  I called a local dealer to find out if I could replace just the terminal blocks and he said I had to replace the panel and gave the part number to me, said he would order it for me.  Went the Monaco site, put in the part number and ordered for $50 less than what the dealer wanted.  I should have it next week.  BTW, the part number is 10106231 for the one I have.

I don't mean to be argumentative, but the main breaker's label says CAT NO: TB250 which would make it a Thomas & Betts breaker. Square D would be QO or HOM in this form factor.

Edited September 10, 2020 by trailmug

[Dr4Film]

Don,

In your 2001 coach, is this the Intellitec EMS Load sharing panel where the breakers and buss bar were destroyed? Based on your photos it appears to be but just wanted to ask to be sure.

The breakers inside my EMS panel are all Cutler-Hammer circuit breakers and the secondary house panel adjacent to the brown EMS panel is a Square D Panel with Square D circuit breakers.

Edited September 10, 2020 by Dr4Film

[quick_tox]

Right side of the main breaker failed, resulting in high resistance, resulting in heat, which cooked the bus and breakers plugged into it. That's my guess.  You're lucky you caught it in time.