I saw an interesting add in Trailerlife Magazine on RV Air (RVAIR.COM).
The company advertises inexpensive air filter housing to install over existing inside grills of RV roof AC's. Has anyone tried this product yet?
It looks like a good idea since current air filters in roof air conditioners are crude and archaic. This product features a stick-on housing that appears to allow insertion of a more significant filter element. It might even help muffle the roar of roof ACs.
Here's the link:
RV Air Filter By RV Air | Purify The Air In Your RV