ResMed AirSense 10 Burn Smell

[Hydrangea]

I'll be starting a new thread since I believe my problem is different than this one and I don't want to keep hijacking this, but I did want to update and say changing the type of filter from the white disposable to the gray washable foam didn't end up helping much at all.

That's good to know. Thanks for that update.

[ClydeSDALE]

I've been following this and other similar discussions for a while now.  The smell that goes by many names and descriptions has been a problem for me also.  I've tried all the 'easy stuff' without results.  When my first Air Sense 10 did it I thought that the machine was self destructing inside.  I tentatively blamed it on the repeated use of my So-Clean machine and the exposure of the pump internals to the ozone. I've never had this problem with any of my previous machines.  Having no other issues with this machine I made the mistake of ordering another one just like it but assembled a plug insert for the water reservoir that during cleaning blocked the So-Clean air flow from entering the machine; just looping from the tank, through the hose and back to the mask and the So-Clean compartment.  Nope, no difference.  I believe it is an internal machine component that generates 'the smell'.   My new machine now periodically smells as bad as the old one I threw out and it's internals were never exposed to the ozone.  The smell came and went most of last night and I'm about DONE!

Thank you EnsignRo, I got all excited about the possibility of it being filter particles getting into the works.  That would be something I could do something about. Now that seems to be another futile attempt to make sense of this continuing and apparently wide spread problem.  I do intend to look into that aspect further though.

It's a shame-shame-shame-on-you thing that ResMed does not appear interested in solving this widespread and disgusting problem.  I'm sure a recall would be extremely expensive so it appears they choose to look away.  The next time I have a stinky night like last night there will be another Air Sense 10 leaving the house and I will guarantee anyone who cares to listen/read there will NEVER be another ResMed product in my bedroom.

[mnsegler]

I just woke up once again to the very nasty burnt smell on my Resmed Air Sence 10 Autoset. I have done this numerous times because I forgot to fill my humidifier. I am not at this time using a heated hose. The smell is coming from within the humidifier when it runs out of water. Running dry is the only time that I get that nasty stink. After refilling the reservoir the smell will go away after about 15 minutes to half an hour.

I have the exact same problem whenever the humidifier reservoir runs dry. about 11 months ago, I replaced the reservoir tank and now I get the smell randomly even if the reservoir is not empty, though it's often getting low. I took the CPAP machine in for service and now I get the same smell in in the rental machine when the reservoir runs dry, so it's not just my machine. Smell is so different from person to person. I describe the smell as a bit electrical but also a sweet, maybe nutmeg oder. It wakes me up but it's not objectionable or horrible. Still it can't be good for me and I need a solution.

[mnsegler]

I experience this with both my ResMed and my DreamStation. The key is to not run out of water.

You can raise the humidity in the room by using a humidifier. 

And/or you can adjust the heat & humidity settings on your CPAP so they 1) still keep you comfortable, but 2) don't run you out of water before it's time to wake up.

P.S. I think the burnt smell is the minerals that were left behind from the evaporated water, being burned onto the bottom of the humidifier reservoir.

Interesting theory about the minerals. But why would there me minerals in distilled water which all I have ever used?

[Sleeprider]

Let me take a stab at why evaporation may leave residuals in a humidifier tank that is only filled with distilled water. Distilled water comes with low, but non-zero levels of contaminates. These concentrate by evaporation, especially if the humidifier chamber is refilled without rinsing or cleaning. Also, a large volume of air is drawn across the surface of the water. This exposes the water to any dust, pollen, spores and other contaminates in the room air. The filter is nearly transparent to these sub-micron particles. It is possible to have a bacterial slime form even in a water chamber filled with distilled water because the bacteria are airborne and exist in most homes, especially baths. When the tank goes dry, any contaminates dry on the warm platen surface and emit odors.

[Hydrangea]

Interesting theory about the minerals. But why would there me minerals in distilled water which all I have ever used?

I wonder that, too.

I wrote that a while ago.  I've since moved somewhere with extremely hard water, such that I cannot use it for my humidifier.  So I've switched to distilled, and it has been divine!  I very rarely get anything at the bottom of it, even though it runs dry every morning.  I notice if I use my tap water for rinsing it or cleaning it, it'll get the minerals even though I use distilled when it's in use.

[DaveL]

Some of us may have different habits.
I top up my humidifier tank, and I use city water.
Maybe I should dump the tank instead. I have a buildup of mineral on the floor of my tank.

And neglect....last night I forgot to fill my tank. I got up early at 5:00, then later returned. Tank was empty and the air smelled as if it was burnt. I forget about a couple of times a year....

[Travelmark]

I have had the same experiences with two different ResMed AirSense 10

[BuckarooBanzai]

I turned on my Resmed AirSense 11 and smelled something burning. It was a mild 'short circuiting' type of smell. It stopped after a few minutes. Thought perhaps it was the tubing on my new P10 mask, so I switched it out for an old P10. Problem continued. So, I switched out my ClimateLine hose for a new one. Problem solved.

Anyone ever had their ClimateLine short circuit, burn out, catch fire, whatever?

[JimInPT]

I turned on my Resmed AirSense 11 and smelled something burning. It was a mild 'short circuiting' type of smell. It stopped after a few minutes. Thought perhaps it was the tubing on my new P10 mask, so I switched it out for an old P10. Problem continued. So, I switched out my ClimateLine hose for a new one. Problem solved.

Anyone ever had their ClimateLine short circuit, burn out, catch fire, whatever?

That's a very good question!  I had the smell this morning after 7 hours of sleep, for the very first time in almost four years of 99.99% compliant usage, along with a totally-empty and dry water tank - also for the first time ever (I usually run low overnight, but rarely less than 1/8" left and never dry).  I was worried about machine failure, so found this thread about the likelihood of it happening due to empty water tank.  For the first time ever, I took the control out of Auto, moved the humidity setting from 4 to 3 to see if that conserves water, and the air temp from 81F to 78F for the same reason.

I'm interested in your theory of a ClimateLine failure, so with a full water tank tonight I'll pay close attention to how things go; thanks for the thought about that.

BTW, does anybody else think the latest ClimateLine hoses are worse than before - specifically too rigid and stiff, not "breaking in" over time?  I use them far past the DME changeout periods, and may even switch back to an old flexy one just for convenience.  Have never had one of these hoses fail on me.