Rain Out

[jrv331]

For the past few days I've been getting rainout in my hose and would like to turn the humidification down a bit, but would like some guidance from the experts. I have a Resmed Airsense Autoset 11 with the heated hose and my climate/humidification settings are all on auto. If I turn the humidification to manual what setting should I start with for the humidification and hose temp to go one level below Auto? My machine is below my head level if that matters.
Thanks

[Pugsy]

The "auto" setting for humidity is roughly equal to about 4 (maybe 5) when comparing to the manual settings for humidity.

You can reduce the humidity setting and it may or may not resolve the rain out issue.
Alternately you can just change the heated hose air temp from "auto" and increase the hose air temp. That's what I do because my nasal mucosa simply don't like less moisture and when the nasal mucosa gets mad at me they make my life miserable with some rather ugly nasal symptoms just related to the mucosa getting dried out.

There is no guarantee that just reducing the humidity setting will resolve the issue. I know people not using water in their humidifiers that still get rain out from the moisture in their own exhaled breath condensing in the mask or hose.

You have multiple options....see posts number 2 and 3 here
http://www.cpaptalk.com/viewtopic/t9403 ... -road.html

[D.H.]

BTW, I don't think that anybody mentioned this, but make sure the machine is lower than your head. This will allow any condensation to flow back into the tank, rather than into your mask.

[jrv331]

Thank you, but just for clarification I would turn the hose temp up not down?
Thanks again

[Pugsy]

Thank you, but just for clarification I would turn the hose temp up not down?
Thanks again

Warm air will hold on to more moisture than cool air....so to reduce condensation from forming you need to INCREASE the hose air temp.
How much of an increase???....we don't know because it varies with the ambient temperature in the bedroom.

The "auto" for hose temperature doesn't seem to use a set hose air temp that I can find and again how well "auto" might even work is going to depend on the ambient room air temp. I tend to keep a rather cool bedroom ambient temp and I found that "auto" for hose air temp just didn't /couldn't do a good job for me but that's not unexpected since I like a cold bedroom.

You may need to just play with minor changes and/or add a hose cozy to the mask's short hose (I have had to do this) if your mask has a short hose as part of the mask. My mask has a rather long short hose and I have max hose air temp AND a hose cozy on the mask's hose and I still sometimes get some condensation at the mask level.

BTW....having the machine lower than the mattress isn't as fool proof as people might think. Often condensation forms in the mask first (our own exhaled breath adding moisture to the incoming humidified air) and if there is any place that water has to run uphill it just won't happen because water can't run uphill. So water in the mask is unlikely to be able to make the trip down the hose because most of us have a bend of some sort in the hose somewhere. Just put the mask on and look to see how the hose is routed...if there is any low spot anywhere the water is going to pool in that low spot. Water can flow uphill...just can't do it.

[jlsmithseven]

I've tried almost every combination on the manual setting for temp/ humidity and could never get a good balance where the air was warm enough without rainout. I've exhausted all of that and just keep it on Auto now which never gets rain out and keeps it semi-warm enough. I find that if I have the end of the hose under the blanket it helps a LOT. I've tried the hose covers but they are very very heavy.