HVAC combustion air vent?

[ryoung7 (ROBERT YOUNG, CMI)]

@sdarden

refrigerant lines

Call it out.
No utility should pass through an air duct system.
HVAC systems have priority to all other trades and there should be no conflict with the duct systems.
Thank David Anderson for the InterNACHI forum in 2006 post.

Freon lines in return air plenum

I would like to know what others think about having electrical wiring, freon lines, ect. in a return air plenum/chase. Seems that the majority of HVAC systems that sit on top of a platform in a closet allmost always have wiring and such in the plenum. Although I have read articles that these conditions should be reported because of having possible hazardous matarials in the plenum. I know that some areas will not allow you to do this. Any comments would be appreciated. Thanks