How do I stop this rainout?!?! Please help

[tierdal]

(double post, cant delete)

[SarcasticDave94]

There's probably 2 things you can do, get a long hose cover to insulate the entire hose including mask extension.

You may need to edit the humidifier settings regarding mode. If it's on manual, you may need to change it to auto, or the humidity number needs to be dropped.

[tierdal]

Any recommendation on tube cover?

[robbob2112]

If you pull the tank after a few hours use is the bottom hot or cool?  If it is cool could be the heater under it has failed.  If it is hot it is time for a hose cover, something like this, make sure the length is correct... that pap machine looks like the airsense 11 verse the autoset 10 listed in yours profile.  Look at the link below

https://www.amazon.com/gp/product/B08MBQ7KXD

[tierdal]

Sorry I got a replacement and they upgraded me and I did not update my profile.

I turned off the automatic stuff. Set the temp to 86 and the humidity to 3...that seems to have fixed it but I have no idea what the proper humidity should be. Do I just wait for my nose to dry out/get damaged by lack of humidity before knowing to up it? 

It is crazy to me the automatic settings just dont work anymore - 2 years and never had an issue

[robbob2112]

So the physics of the situation apply all the time.  You get rainout from humid air and the tube being at different temperatures.  That is from the humid air being warm from passing over/through the warm water into a colder tube.

You have verified by touch that your tube temp is working.  It may or may not be at the right temp but leave that for now.

The automatic circuit uses the sensor at the mask end of the tube to collect temperature and humidity of the air ... the sensor being housed in the little piece of plastic sticking out into the airway where you mask connects.

If the temp is below what it should be it turns on the tube heater.  The heater is off and on, there is no in between - so it turns it off when the temp is high and on when the temp is low.

If the humidity is lower than it should be it turns on the heat under the tub to put more moisture in the air.  Again it is either off or on and the only thing that will turn it off when the humidity is low is if the thermal fuse under the plate is blown either through over current or over temp.  The fuse is a tiny little rocket ship shaped thing with a wire out either end.  It blows if current is over 5 amps or if temp is over 98c.  Might be 93c since it seems to be hard to find the 98c ones.  Either way 100c is boiling for water so it turns off just shy of boiling.  There is also a thermistor (temp sensor) built into the heating plate to control it's temp so as not to overdo things and have an overshoot blow the thermal fuse.

By default the automatic circuit aims for 80f and 82% humidity.  This works out to be a tube temp of 80 and humidity level of 4.

Now combine the moving parts..... if the tube temp is low it turns on... but if humidity is low it turns on the water heater until it senses the increase at the end of the tube.  By being on it heats the air as well so the tube temp will be high and it will turn off because of it.  Things continue to cycle off and on until it all reaches equilibrium in the end and the on/off cycles become shorter because it only takes a minor change to bring things back to equilibrium.

So a rainout is caused by things being far enough out of wack things can't be compensated for.

Causes -
1. room air temp change - you said no change - so good
2. hose heater wire fails - you say it heats - so good
3. hose humidity sensor fail - we don't know this unless you swap for another hose
4. tank heater failed in some way - we don't know - you need to pull the tank out after a while and touch the bottom, if warm it is probably fine.

IF and only IF everything above has been ruled out -
5. some unknown failure in the automatic circuit - we don't know  - try to find a manual setting that works and see if that is reasonable - 83 and 3 seems goofy, but we don't know about 3 & 4, either could cause issues.

Beyond those if everything appears to be working get a hose cover as mentioned many times before.

[tierdal]

Thanks!

[robbob2112]

One more note, i have my tube temp set at 72 and my humidity level set to 7. With a hose cover I never rainout.

Let us know what you discover with regard to items 3 & 4