Warm AFCI Breakers

I would appreciate all feedback on this.

I consistently see the AFCI breakers warmer by several degrees than the rest of the breakers in the panel, especially when they are in a bank of AFCI breakers. From the research I have found, this is apparently normal.

I am wondering why these particular breakers are consistently warmer. Do others out there call this situation out in the report ? I am also wondering what the long term effects will be if a bank of warm AFCI breakers is present in an electric panel

I have attached a thermal image from this situation I saw today at an inspection.

Thanks in advance all…

Jonathan Leahy


AFCIs contain a power supply and a circuit board that monitors for arc conditions.

They consume power and that produces heat.

1 Like

John McKenna? Oh, John…

… Oh never mind his representative Mikey is here!

I am sure that they do. But what difference would that make?
You personally should never call any situation you see using thermal imaging that you do not fully understand. In short you should never point your camera at anything that you don’t know about (or have someone there with you that does).

Now that you own a camera, it’s time for schooling. Not just Thermal Imaging, if you can’t tell us what heat does to Electrical Devices you need to start back at High School Science class.

This is your “reality check”, now everyone else can chime in with warm and fuzzy free training (to show the world how much “they” know). Then you can get a sticker for your web site that says your “Certified” (Federally no less!).

Sorry, I got out of bed without my “Tact” this morning…

I’m not a thermographer, nor do i own a thermal camera, and i have never used one, but I’m sure you know elecric devices generate heat. Based on the scale of the temperature differences in your image, i dont think theres that big of a temp change from surrounding areas to the hot area. Perhaps if you had a larger disparity in temp (like ambient temp of 70, and the hot spot like 150) it would be an issue, your image is only like a 18 degree difference. Color differences for the sake of it arent a defect.

What a tool.:roll:

I am not MkKenna’s mouthpiece butt head.

If you take issue with what I said, say so and why.

They all run warmer and so do GFCI. Any breaker over 140 degrees are a problem but I’m not sure what yours reads because I don’t do Celsius.

David, maybe you should not get out of bed. That way would not always be in a bad mood.:smiley:

This board is for learning. Everybody should be encouraged to ask questions. NACHI does not have near the sheep followers as other message boards.


back at you Mikey!

If all you idiots can put up with the likes of this clown, I don’t know why you have a problem with the truth!

There is about 35 pages of responses that I could come up with as to what’s wrong with this original post. I was trying to keep it light, but I guess there ain’t no please’n any of you.

I can even hack on the responders to the original post. Such as, your temperature differential is not even close to being a temperature differential if you don’t adjust for apparent temperature. No one is immune.

I’d just be happy to see somebody “try” to get it right for once.

If somebody doesn’t like what I have to say, prove me wrong (for once), otherwise shut your mouth.

I answered the OPs question in post 2.

I said nothing about the thermal image.

Wake up Andersen.

Get a job Larsen…

Typical. :roll::roll:

The OP asked a question about the heat produced from AFCIs.

What did you add to this thread?

The fact that there is insufficient information and that improper use of test equipment is a liability to your existence.

The fact of what heat has on the electrical system. Why the hell would anyone use thermal imaging on an electrical component without knowing what the effect is?

Post temp differentials without proper temp correction (which changes things).

The fact that a triac in the device produces heat.

Knowing how hot is really “hot”.

But, you don’t have to worry about that. You just camp your *** on this board all day…

Are you getting a hard-on over the conflict yet!?

if you want to speak to the applicability of using a thermal imagery to determine how much heat is too much fine.

I chose to answer his question which is all he was asking for.

Your triac theory is simply wrong as the triac only passes current AFTER the detection circuit detects a fault that meets the criteria of an arc fault.

If you are able to read a schematic this should be plain to even you.


I think somebody needs to have their nose stuck in the corner until he can prove he can play well with others.:shock:

Do not let David bother you. It is better to ask the questions and get the answers, than to not know the answers.
Ever since David joined NACBI, he has be going off on NACHI members. I only went to their board once and they were attacking a NACHI member in one post and bad mouthing NACHI in another. Reminded me too much of InspectorNews or what ever that wantabe message board is.

You can pull my past post and prove this, I’m sure…

You couldn’t even imagine where NACBI started “ye old wise one”…

As I said, you tolerate Mikey’s crap all day and night (33,000 posts and rising) but have to tell others to go stand in the corner. So what makes anything appropriate vs. non-appropriate around here, belonging to the wrong club?


You posted untrue information when you stated the triac caused the heat.

Get over it and learn something.

And thank you for the link you posted. I didn’t think about the bimetal component.

John Bowman started NACBI. John Bowman tried to take over NACHI and leave Nick high and dry. Members found out about his plans and ran him out on a rail.
Bowman tried to start his own home inspection organization and failed.
Then he found some inspectors that Nick refused to play ball with and NACBI was born.
Would you like any more history. I got a really good memory of people who have tried to screw NACHI over.

All I am saying is you just need to calm down some, David. I just do not want to see you make enemies here. Larson is a good guy and he was just answering the newbie’s question.

Interesting comment as the majority of the initial members still belong/post here.

Mr. Leahy, when you have your spot on a suspected anomaly make sure the spot is fully inside the suspect area and not as
your image shows. A better spot would have been farther to the right and not include the handle opening

Interesting string here all.

Thanks for the input