I inspected a panel that has 2 black wires & 2 white wires going to a single AFCI breaker. Am I right that this is a double tap?

A single white wire should be incorporated as part of the breaker… not an additional wire…
I know of no “double” or tandem AFCI breakers out there, so I would have to assume you are correct about the double taps. Got a pic you can post?

Do you have a picture?
Help us help you.

Here is a picture attached

That is double tapped. With a shared neutral…double trouble

Yes, that is incorrect. It is double tapped.

Agree with Brad and David.

In the same panel I took this picture. Does it look like scorch/ overheat marks.

No. Not in my opinion.

No problem there, but the early post is double trouble.:shock:

I initially saw a two pole breaker.

The hots are on opposite legs. This is no different than any other multiwire branch circuit.

The two wires in the terminal is an issue.

Looks like shadows from the cobwebs and dirt.

Where is the shared neutral? If this breaker were listed for two conductors per terminal there wouldn’t be an issue.

Ok guys, help me out here. I see a one pole AFCI breaker that has two circuits connected to it, and only one neutral returning to the neutral bar. Why is that not a shared neutral, and what Siemens breaker allows two conductors?

If that is a single pole breaker you only have one circuit with two leads. That does not make two circuits.

Two leads with one neutral. I still don’t understand why this would not be an issue. It seems to me this would be the same as a MWBC on the same phase, would it not?

One circuit only needs one neutral.

Ok, I am seeing some clarity now. There won’t be an overload on the single neutral if sized for the breaker. I’ve never seen a double tapped AFCI or GFCI breaker before, Thanks.

It is no different than two leads splitting in a junction box into different directions.

I assume that pigtailing two neutrals into one lead to the neutral bar (in the panel) would be an issue though.