Suitable Disconnect?

Note the circuit breaker on the air handler itself. Is there anything that says the disconnect has to be separate from the appliance?

Nope. An integral disconnect is permitted as long as it disconnects all of the ungrounded conductors.

Please explain why this one does not.

Also, what code to rely on? Could not find it during a word search. Thanks.

I believe RM meant the Nope to mean it does not need to be a separate disconnect and that the unit switch is fine to serve as a disconnect.

NEC 422.34 Unit Switch(es) as Disconnecting Means. A unit switch(es) with a marked-off position that is a part of an appliance and disconnects all ungrounded conductors shall be permitted as the disconnecting means required by this article where other means for disconnection are provided in occupancies specified in 422.34(A) through (D).

Thanks guys, yes that is what I meant in response to Joe’s question “Is there anything that says the disconnect has to be separate from the appliance.”

Is the disconnect fastened to the dead front in such a way as to cause a hazard when the cover is removed?

No. Historically, those are almost always Square D QOU breakers. They clip on DIN rail. They have line and load side lugs. They still present energized terminals to the person who takes off the appliance cover. If you are an employee of an inspection agency, it would be flatly illegal for you to remove that cover without proper training and PPE. Owners, feel free to do as you please.