Odd Smell/Odor

Grit dog wrote:

Gdetrailer wrote:
Is the odor smell more like "dirt" or "earthy" like?

OP said chemical smell...

Depends..

Mold, mildew and wood rot from well hidden water leaks can smell like a lot of things, often like damp dirt or "earthy", musty smell.. Musty smells can sometimes smell a bit like "chemicals" and will have a long, long "hang time" in soft absorbent items like clothing, bedding items even when you have removed them from the source for days and even weeks.

OPs RV should have enough age now that most "chemical" smells from glues, plastics, carpeting, flooring should have dissipated by now to the point of not being detectable.

Odors from black tank if they use chemical treatments can and will hang for very long periods of time, persistent odors from heavy black tank chemical treatments are very possible if the toilet blade seal is not working as it should or you have bad gasket between toilet and tank.

Odors from a malfunctioning air admittance valve are NOT going to smell like chemicals unless someone has dumped a chemical treatment down a sink drain. Instead you will get a highly nauseous sour smell a lot like dank, stale swamp water.

Mice can be an issue though, they use everything as a "litter box" and their urine is extremely pungent and has a heavy AMMONIA component (chemical smell), they love to burrow into fiberglass insulation and saturate it with their urine and high moisture in the air and or high temperatures seems to bring the odor back with a vengeance..

I am betting the OP has severe hidden water damage with lots of wood rot.. OR they have a severe mouse infestation with lots of nests.. Both cases would require some major surgery to walls and ceiling..