I figured I'd chime in. I just bought a hepa purifier for my room, it really dries me out. Granted I haven't slept in my room in a week given that I had black mold develop in my closet (apparently baby bottles can grow mold during long term storage even after being washed and sanitized, lesson learned.) at any rate, i took everything out, new bed, new bedding, cleaned everything that could be cleaned and threw out anything that couldn't (any linens, clothes, etc. Washed down the walls with palmolive and water, vacuumed the shit out of the carpet. At any rate I'm not entirely sure whats causing my dry air issue, I'm thinking it may be the purifier. I'm buying a mold test kit today so we shall see within 48 hours if I got it all. Anyway, sorry for the long post, just seems the heap filter may be contributing to my asthma.