Insurance is still giving me the runaround on my UARS and I found a Respironics BiPAP AutoSV Advanced on craigslist. The seller said it had no issues and no cigarette exposure, but I got it in the car and the cigarette smell was really bad, like keep all the windows down on the ride home and leave it outside bad! Seller ghosted… It also has about 5400 hours, but it was a lot cheaper than going to a secondhand CPAP store.
To clean it, I started by running it with a large ozone generator for about 24 hours total which helped significantly, but it was still bad. I knew I had to do a complete tear down and overhaul. I managed to clean all the intricate components with rubbing alcohol and ozone, but the foam air intake chamber is retaining most of the smell.
The air intake is open-cell foam similar to neoprene. I started with ozone for several hours, then several hot water and dawn soap washes, still smelled like a dingy bar. I was worried using isopropyl alcohol might degrade the foam, but had to give it a shot. Several washes gave off strong, yellow tar residues, but the foam started to fall apart. Did another round of soap washes.
The blower, silicone tubing, ASV valve are all passable and the foam components kind of passed the smell test by this point. I rebuilt the unit and glad it came back on with no errors, sensors seem to be working properly, but the smell from the foam is still really noticeable and its unusable.
The majority of the foam is ultrasonically bonded to the plastic base and chamber cover – the 2 inserts are about a 1/4 of the surface area, so I think the best solution is to seal the foam. I’m trying to figure out a non-toxic sealant that would be suitable and close to medical grade/inert.
paraffin (potentially toxic), natural waxes, Elmers school glue, 100% silicone, natural glues. Some kind of water-based non VOC sealant?
PS: Be very careful with ozone! It has a half life of 24 hrs and even outdoors it was very powerful.