Heat Pump airhandler in basement closet

Finished basement (walkout).
Heat Pump air handler and electric heat strip located
in an interior closet with 30" louvered door.
Client says his brother was told needed exterior rated
door with threshold and weather stripping.
Never heard this before and can’t find any code requirement.
What say U?

got any pics?
With the a/c or heat on, is the door hard to open?
Is there a lot of dirt/dust build up around the door or in the closet?

New house John.
I had no issues until client asked if solid door with
threshold and weatherstripping was required.
Can’t find any code reference that deals with it
other than clearance requirements.

I don’t think there is a problem. I have never seen an exterior rated door indicated for this aplication.

It doesn’t even need to be in a closet, much less a sealed closet. . .

Sounds like the requrements fo natral gas in enclosed area.

Thanks everyone for your responses.
A “Non-issue” is where I was and still am.
Thanks again.

They can change out that door and make things quieter so long as there is a return air duct system.

If this is a free return design, that is the reason for the louvered door.
There would not be any duct work at the bottom of the air handler.

No need for louvered door, because there is no combustion question, being an all electric system. Clearances still a question, but typically 1" clearance on an all electric (kw strip heater - internal mount is no problem) AHU. I’d want a solid door w/ weather/sound dampening gasketing for noise purposes. Wood would/should meet local code.