Caution for DreamStation users

[Hydrangea]

Well, I finally figured out 2 things:
- Why "they" say to change your humidifier water daily.
- Why ResMed has the cool-down feature after you shut off their machine in the morning.

Mold/mildew wants to grow under the lid of the DreamStation humidifier!  

Ack!!!

I flipped my lid up the other day and saw it growing in the inside of the lid.

Since then, I've been pulling the water chamber out each morning upon waking (or at least just opening the lid).  And the water is so warm in there.  Duh, no wonder mold is eager to grow under the lid. 

And genius ResMed.  I thought it was just a quirky weird electronic thing for the AirSense 10 Autoset to run a cool-down in the morning. But no, I bet it's to cool off the water so it isn't as likely to create mold!!!

So, FYI to you DreamStation users: at least open your lid each morning, if you're not dumping the water each morning.

[MitchS]

I found adding the humidifier lid seal and the seal between the humidifier and blower to my weekly cleaning schedule eliminates the mold and mildew problem with the DreamStation. I do the same with my ResMed machine. There is still condensation on the inside of the humidifier tank, even after the cool down period, so it is still possible for mold and mildew to grow in the ResMed humidifier as well.

[Sleep2Snore]

The first thing I do when I wake up is pull the humidifier chamber out and switch the machine OFF at the wall.  Then when I get out of bed I go empty the water out, give it a rinse and leave it open to dry upside down.  Then early evening I fill it with fresh water.  Every week I wash it with soap and water.
Easy for us as we have switches on our sockets.  Resmed have a better system where the machine run at a low level until it is either started again or cools down the humidifier a bit.  I don't think it cools it right down though to stop mould (mold in US).
They say to empty and change the water every day, so why leave it, nice and warm to grow mould/mold and grow bacteria!
Distilled water is fine, but as soon as you open it it is no longer sterile and if you buy it by the gallon, there could be a lot of bacteria on fungal spores in it by the time you finish it.
But then the fashion is to buy bottled spring water and it might just surprise you what is in there.
They do test it for bad things, but everything else has to be below a certain level.

Mold just has this shock moment, some of it will do you not a lot of harm, but other mould/mold can have serious problems for your lungs and 
respiratory system.  Might even be worse!  So keep everything clean and change the water.

[SarcasticDave94]

Good info on the humidifiers for both brands. Thanks. I did wonder why ResMed had the cool down function.

[MyronH]

I take my resmed chamber off every morning. Dump any remaining water. I use distilled water only. Then I use CleanSmart disinfectant spray and spray the inside of the chamber and let it sit upside down open during the day to dry out. That spray smells like chlorine or something but it dissolves into normal saline.
I pour it in my hose occasionally too and clean my hose with it. Haven't noticed any mold so far.

[CB91710]

They call it a "cool down" cycle, but all it is is just a low air flow through the system with the heater turned off.  It is not a refrigeration system and will not cool to below ambient.
Preventing mold would require lowering significantly below ambient.
The main purpose of the cool down, IMHO, is to help clear the tubing and mask of condensation.

[Nightowl4]

I used to have a Sullivan and it had a large water chamber so I would leave the water in it all week. It never got mold that I could see but the stainless steel had some slippery slime so I started washing it every other day. Now I have the Airsense 10 and have to wash and fill it every day. The chamber only holds enough water for one night. By morning it is almost dry. I always use distilled water because I don't want minerals on the metal surface.

[Perchas]

I solve the problem by freezing the humidifier every day, leaving the lid open. I also breathe fresh, moist air as if I were in the mountains.

In winter I put the humidifier in the middle position, but I still get hot, humid air that I don't like.

It's a good habit to wash your nose of gossip every day.

[Melman]

They call it a "cool down" cycle, but all it is is just a low air flow through the system with the heater turned off.  It is not a refrigeration system and will not cool to below ambient.
Preventing mold would require lowering significantly below ambient.
The main purpose of the cool down, IMHO, is to help clear the tubing and mask of condensation.

This correct. In fact molds grow well at refrigeration temperature.  Back in my lab days we would often find mold growing in refrigerated petri dishes. The appearance of mold must be a function of the local environment. I just top off my humidifier daily and completely drain and refill it once every week to 10 days. I may actually wash it with mild detergent every month or so. I have never seen mold. I use distilled water to avoid mineral deposits but I don't think that matters. I suspect grocery store distilled water is as likely to have mold spores as tap water.

[ardenum]

Mold grows easier if it has spores in the air. I can not wash my humidifier for months and i always put water at 80 degrees C each night, both the tank and the hose have droplets in them. I get pneumonia easily if the air is cold. This can go on and on and no mold grows. I also know there is no mold in my house, its completely made of concrete and the insulation is strictly at the outside, plus I have air filtration. If you have mold in your tank after just weeks I'm pretty sure you have mold in your walls.