New machine adjustment

I've been using an old CPAP m-series for 10+ years. It's a "true" CPAP in that its fan is set to run at one speed. I've just switched to a Dream Station which, since is technically an A-PAP, in order to maintain a precisely constant pressure is speeding up and slowing down according to my breathing. I think the fan on this machine has a slight whine to it as well. Anyway, it's driving my wife nuts. She never had a problem with the old machine, but the new one, she says, sounds like an old car with a worn out AC motor speeding up and slowing down over and over.

Any suggestions? Is it possible this particular machine is faulty?

If the noise is loud enough to bother the wife then I would take it back and tell them the motor noise is excessive.
It shouldn't be that loud.

Happy wife....happy life.

Tanuge wrote: ↑

Thu Jun 13, 2019 6:48 am

I've been using an old CPAP m-series for 10+ years. It's a "true" CPAP in that its fan is set to run at one speed.

Not true, It varies the speed just like the System One, System One 60 series and the Dreamstation. While you (or your wife) may not have *noticed* this... it still did it.

Tanuge wrote: ↑

Thu Jun 13, 2019 6:48 am

I've just switched to a Dream Station which, since is technically an A-PAP, in order to maintain a precisely constant pressure is speeding up and slowing down according to my breathing.

There's no 'technically an apap', it either IS an apap, ie, Dreamstation Auto, or it's NOT an APAP, (ie, Dreamstation CPAP or PRO models.

APAPs vary their set pressure over a period of minutes, in response to breathing events. CPAPs don't.

They *ALL* vary their blower speed with each breath, because otherwise, the pressure would DROP when you inhale and the pressure would GO UP when you exhale.

Tanuge wrote: ↑

Thu Jun 13, 2019 6:48 am

I think the fan on this machine has a slight whine to it as well. Anyway, it's driving my wife nuts.

Respironics machines run their fans at a speed that causes an audible whine for people with decent hearing (depending on the pressure they're set to).

I sold my Respironics System One 60 series machine for just that reason, and bought a Resmed S9. It's fan doesn't make an audible whine.

I thought it was just me .... I just switched from a the ResMed Philips System One 150 to the Dreamstation. I decided to try the Auto CPAP feature and I can definitely hear the fan speed up and slow down if ever so faint. I never heard anything with my System One.

Since I've only had it 5 days I'm going to use it on the Auto CPAP feature for the rest of the week because I'm interested in the stats and to make sure the pressure I've been using for the past 10 years was correct. But since I'm already use to the constant pressure I may change it to the a fixed CPAP if the noise goes away.

Again, the noise is really not very loud and doesn't stop me from falling asleep, but it's definitely there.

tapau wrote: ↑

Thu Jun 13, 2019 7:44 pm

I thought it was just me .... I just switched from a the ResMed Philips System One 150 to the Dreamstation. I decided to try the Auto CPAP feature and I can definitely hear the fan speed up and slow down if ever so faint. I never heard anything with my System One.

Since I've only had it 5 days I'm going to use it on the Auto CPAP feature for the rest of the week because I'm interested in the stats and to make sure the pressure I've been using for the past 10 years was correct. But since I'm already use to the constant pressure I may change it to the a fixed CPAP if the noise goes away.

Again, the noise is really not very loud and doesn't stop me from falling asleep, but it's definitely there.

Again, the 'auto' feature varies pressure over many minutes, not with each breath.

Perhaps your pressure on the old machine was different than what you have when you tried the new machine in auto mode.

The pressure will change what pitch the fan whines at.

Tapau, I wonder whether the change in pitch per breath comes from pressure support. At any rate, I have used both a PR machine, for a week of titration, and the ResMed AirSense 10 Autoset, which is now my regular machine. The latter is definitely quieter, and the sound of the PR definitely bugged me.

Miss Emerita I think it is from the pressure relief. Can't be sure what I set it on, but I think it's on '1' which is the least pressure relief. I don't think I can turn it off when it's on Auto CPAP mode.

Thanks

tapau wrote: ↑

Fri Jun 14, 2019 8:40 am

Miss Emerita I think it is from the pressure relief. Can't be sure what I set it on, but I think it's on '1' which is the least pressure relief. I don't think I can turn it off when it's on Auto CPAP mode.

Thanks

Zero is the least pressure relief, you can turn off *flex.

Even when you do this, the fan speed still changes as you breathe so that the pressure stays constant.