Humidifier almost empty after 1.5 hours of sleep

[MapleLeaf84]

Hi guys, I'm trialing a ResMed AirSense 10 with a full face mask. Last night I took it off in my sleep after 1 hour and 19 minutes. The humidifier was full with distilled water when I went to sleep, but after just that short amount of time, it's almost empty. I keep my room as cold as possible, could this have caused it? Also, I woke up quite congested. I have noticed previously that the depletion rate of the water varies, but usually even after 8 hours there's still a safe amount left.

Please help, I'm scared to use it again because I don't want ruin the demo machine if the humidifier runs totally dry.

Thanks!

Edit: I just remembered another thing: for the last couple of weeks the machine has been stowed away in its case, initially due to being ill and then to prepare for and conduct another home sleep study (the Respiratory Therapist advised me not to use CPAP for a while before the test because he said CPAP might lower the AHI, and I needed as high an AHI as possible for insurance coverage). Could this also have caused it, being unused for a couple of weeks? I now remember there being some sort of a warmup feature on the machine, should I have used it?

[JDS74]

Just speculating:
Cold air is dryer than warm air and would cause a higher evaporation rate in the humidifier. It shouldn't be this dramatic though. Are you experiencing rainout (excessive condensation) in your mask?

Check to see if there is a tiny leak in the humidifier tank or signs of leakage at the location of the machine when you use it.

[Julie]

I believe you are congested from too much humidity and the cold temps don't help. Try warming the room even a little for a few nights and also try a lower (if possible) setting for the humidifier. You're giving yourself a cold!

On the off chance there is a 'micro'' leak in the tank, go over it carefully, fill it and then watch to see if there is any small leak, as well as be sure it's connected properly and not off kilter leaving a seeping 'seam' somewhere.

[Cruiser1234]

As a reference, on both my ASV and autoset, it takes roughly a week of sleeping to empty from the max fill line. I keep my humidity setting on 4 and the indoors is around 50% humidity / 22C.

[Dog Slobber]

1. You forgot to top it off last night
2. There is a heat source near your device
3. There is a small leak
4. When you took your mask off, the machine was still blowing

[chunkyfrog]

You only THOUGHT you refilled the tank--(it can happen)

[zonker]

You only THOUGHT you refilled the tank--(it can happen)

i would be embarrassed to admit how many times that's happened to me.

[chunkyfrog]

You only THOUGHT you refilled the tank--(it can happen)

i would be embarrassed to admit how many times that's happened to me.

Guilty. Several times.
If I wake up at 3 AM, smelling dry tank funk, yeah, I know.

[djams]

We enjoy a cold room too. Good for sleeping.

What's the humidity in the bedroom? We will be getting out the cold air humidifier when the temperatures drop to the point we have to leave heat running all the time.

Out of curiosity, what are your settings?

I like cool air from the machine. I use manual/4 and hose temp off. When this starts causing rainout in winter I put a hose cozy on and have to turn on the heated hose.

Didclaimer: like mask advice, humility advice borders on being useless because we're all different.

[Janknitz]

Do you mouth breathe? That can empty the chamber really fast, whether you are in a FF mask or not. It just can't keep up with the drying of the mucosa in your mouth.

[Legrunt]

Do you mouth breathe? That can empty the chamber really fast, whether you are in a FF mask or not. It just can't keep up with the drying of the mucosa in your mouth.

How does that affect the rate of evaporation?
How does the machine know if it is preventing the drying of nasal vs oral mucosa?

As far as I know, only the rate of air flowing over the water determines the rate of evaporation (and the temperature of the water itself)
and mouth or nose, your lung capacity remains the same.

The only thing I can think of is, if you are on a nasal mask, or pillows, your mouth falls open, the air rushes out and keeps rushing out in a huge leak for an extended amount of time.

[palerider]

Do you mouth breathe? That can empty the chamber really fast, whether you are in a FF mask or not. It just can't keep up with the drying of the mucosa in your mouth.

How does that affect the rate of evaporation?

Because more air flows across the water, thus increasing evaporation.

[Legrunt]

Do you mouth breathe? That can empty the chamber really fast, whether you are in a FF mask or not. It just can't keep up with the drying of the mucosa in your mouth.

How does that affect the rate of evaporation?

Because more air flows across the water, thus increasing evaporation.

I'm still unclear. You mean to say I will move more air by breathing through my mouth rather than my nose? I thought rate of respiration was only dependant on lung capacity?
Unless the nose is obstructed... But then thats a different problem altogether no?

[palerider]

Do you mouth breathe? That can empty the chamber really fast, whether you are in a FF mask or not. It just can't keep up with the drying of the mucosa in your mouth.

How does that affect the rate of evaporation?

Because more air flows across the water, thus increasing evaporation.

I'm still unclear. You mean to say I will move more air by breathing through my mouth rather than my nose? I thought rate of respiration was only dependant on lung capacity?
Unless the nose is obstructed... But then thats a different problem altogether no?

I thought that Janknitz was referring to mouth *leaking*... and higher leaks would cause greater evaporation.