Airsense 10, very quiet, worked perfactly for about 1.5 years. Machine hose heater, not hose, failed. The machine was swapped out for a new one. No humidity, none. I use manuel setting of 8, maximum, then set hose temp to just prevent rainout, about 79 deg. F. Hotplate not warming, swapped for 4 more machines same problem. Water in chamber, press warming, warming light message pops up. Check water temp eith instant read kitchen thermometer, at 5 min., 10 min, 20 min, 30 min. 79 deg F, no change, hotplate cold to touch even though "still warming". Attempted to use overnight, tube temp 72. No humidity, check hotplate, cold. Called a friend of mine with same machine. His machine did not warm either! He didn't notice, likely because his pressures range from 4-6 and he uses full face mask. Thats a total of 6 machines that the humidifier is not functiinal.
Ok, you can guess what my problem is, an incompetent dme that thinks that if the light comes on, its working. Its my problem for whatever reason. I am fighting with the dme to get them to send my machine to Resmed for evaluation. They resist, i know not why, but i will eventually get it fixed.
I wanted to post this because there is a strong likelyhood there are more like mine out there. A novice user, especially with low pressures may not notice, others with dry mouth problems blamed on a mask or whatever. The book states that the hotplate temperature is 154 deg. F, same as older models. Simple test, with water chamber removed press Warmup. Carefully touch the hotplate with your finger. If its working you will be quickly removing your finger as 154 F is very hot. If after 5 to 10 minutes you can hold your finger comfortably on the hotplate, it isn't working.
So if you are having humifity probkems with your Airsense 10, dry mouth, ask your dme to check it out.