Resmed Airsense 10 Autoset unexpectedly loses power

I am seeing some strange behavior from my Resmed Airsense 10 Autoset. I was curious if anyone else has ever seen this behavior.

Maybe six months back or so, I woke up with the machine completely off. I figured something went screwy in the night, so I tried to turn it back on. There was no power at all. I unplugged it, checked the power supply, and plugged it back in. It worked fine after that - for a few months.

Then it happened again. I thought for sure it was something in the power supply, so I used the power supply from my backup Airsense 10 Autoset. That worked fine until a few weeks ago, so then I ordered some additional power supplies (used, but in good condition). I tested the old and new power supplies with a multimeter, and they all were putting out similar (and appropriate) power.

When this happens, if I unplug the machine and let it sit for a few hours, it'll work when I plug it back in. If I unplug and plug it back in right away, it doesn't work. I've even tried it after around 20 minutes with no luck. I'm assuming there is some sort of capacitor discharging over time that is allowing a reset, but I'm no electrical engineer.

Has anyone seen anything like that? I doubt there is anything that can be done with it, but I figured I'd ask instead of just chucking the thing. I forgot to grab the total hours on it before making this post, but it is up there. I won't be surprised if it is just failing, so I'm just asking out of curiosity more than anything.

By "up there", can you say over 17,000 hours?
Or over five years use?
It might be time to look for a replacement.

Sounds like a component overheating maybe? Don't know if there's any known issues with any specific components or anything, but that's kind of what it sounds like to me. I've had this problem with a few hard drives over the years and once successfully used the freezer trick to pull data off an overheating drive. But it's probably not advisable to run your machine in a freezer.

chunkyfrog wrote: ↑

Mon Aug 14, 2023 11:09 am

By "up there", can you say over 17,000 hours?
Or over five years use?
It might be time to look for a replacement.

I looked last night, and I am a couple of days short of 9,500 hours. I think I've had this one for about 3 1/2 years. I'm already working on a replacement, but I do have a brand new backup already on hand (plus a few other, older machines that aren't as good as the Airsense 10 - but would work in a pinch).

amenite wrote: ↑

Mon Aug 14, 2023 7:17 pm

Sounds like a component overheating maybe? Don't know if there's any known issues with any specific components or anything, but that's kind of what it sounds like to me. I've had this problem with a few hard drives over the years and once successfully used the freezer trick to pull data off an overheating drive. But it's probably not advisable to run your machine in a freezer.

I think that's a good guess/observation. I've also used the freezer trick a time or two.

The machine works perfectly fine for extended periods of time...then it shuts off randomly in the night. I leave it unplugged for the day, and it gets me another extended period of time. I'm about ready to move it to its own power strip and just turn the switch off on the power strip every day.

As I said in the other post, I'm working on getting a replacement - and I have a good backup (and older machines in a pinch). Similar to what you were thinking, I figured if it was a specific component that people were having troubles with, it might be something that could be cobbled back together to get just a little more life out of it.

did you try substituting one of your different power supplies for the entire night?

tyrinryan wrote: ↑

Tue Aug 15, 2023 10:17 am

did you try substituting one of your different power supplies for the entire night?

Yeah. I was running on a different power supply the last time it happened. So the one that came with the machine was in use two times ago when it happened. I swapped out to a different power supply and was using it for a while. It then did the same thing with that power supply. After leaving it unplugged for the day, both of those power supplies worked just fine to power it back on. I am currently using one of those power supplies to run it, and it has been fine since the last time it happened.

I was hoping it was just a faulty power supply, since it is a replaceable item. If it is something internal--unless it is a single, obvious component failing--I doubt it can be easily fixed. I doubt it is a single component, though, or else it would probably happen more often/all the time.

Couple more thoughts here, do you have Oscar? Is there any clue in the data, like it only dies when the pressure is maxing out, or heading in that direction? dunno if you can get data right up to the time of it shutting down but could be a clue there.

Also the humidifier heat - any difference with it on or off?

BTW i've read recently that the freezer trick on hard drives is no longer a thing due to the heads on mechanical drives being so much closer to the platters than they used to. Something about ice particles causing irreparable damage. Back when I used the trick it was an overheating PCB that was the issue, not the drive internals, but still.