Why could antique AC go decades without mold
 

Just curious my fathers 1970 era window Ac never cleaned, never moldy

Modern AC, have to clean constantly gets moldy in a matter of weeks, can’t easily get in to where the mold is located either

Temped to toss my moms AC Because it’s moldy and extremely difficult to clean

Hate to have to buy an ac every year because it molds and is uncleanable.

Interesting question how old my air conditioner is.

https://duckduckgo.com/?q=foam+clean...densers&ia=web

Asbestos, lead-based paint, and all copper construction keeps organisms at bay.

Not sure about asbestos, and I remember seeing lead-based paint getting moldy, yet copper is supposed to have some antimicrobial effects.