AC air smells acrid

The atmospheric formaldehyde concentrate in all-new plastic RV's is an absolute danger not merely a hazard.

A strong reason Quicksilver was built from salvaged teak. I am convinced beyond the shadow of any doubt formaldehyde and a strong bacteria has killed many RV'ers.

The solution is to air-out new RV's. Bring interior temp up to 85F then air it out. Five times over a period of one month. 24/7 ventilation during hot summers.

Very few strains of bacteria or other pathogens can live in pure vanilla. The real stuff -- not based on crude oil.

Dilute genuine vanilla diluted ten-to-one. Spray on the media after cleaning. I used to spray a dilute solution of sodium hypochlorite as a rinse after cleaning. Legionnaire's Disease is way more common then you'd think. It kills dozens of elderly RV'ers without being recognized.

When I hear the term acrid, I think electrical.
Any big box home center and most hardware stores will carry aerosol air duct freshener or deodorizer if the problem is in the ducts.

The A/C coils on the roof need a good cleaning, and then your A/C should cool better afterward too.

A little Fabreeze up there will hep too.

Leaving your fan on all the time instead of auto helps too by drying out the coils when compressor is off.

Put some towels on the floor too.

If your coils are like mine were, cleaning makes it cool like new.

Reality-- NO.

Particularly in hot, HUMID conditions, the EVAPORATOR is likely a mold farm.

Only real answer is to clean the evaporator. Any box store has evaporator cleaner.

Only serviced from the roof. Take old rags/towels up to plug the opening to the coach to keep cleaner and water out of the coach.

Basically, an annual servicing in humid climates. "Cures" the wet dog smell when you turn on the A/C.