Dreamstation REVERSED Air Flow!

[SuperSleeper]

Strange.  When Colin Sullivan first invented CPAP, I've heard he first used a reversed-flow vacuum cleaner (a Hoover for you Brits) as his first test CPAP prototype.  Perhaps your machine reversing the airflow was reverting back to it's primal roots.  

But seriously, I've never heard of such a think either.  

Maybe you electrical engineers can tell us - could EMI from the Pulse Oximeter set on top of the CPAP somehow interfere with an electrical switch on the blower in some way, causing it to reverse direction?

[Wrenchtwister1]

As an automotive technition, the only thing that could cause that is motor reversal. there are no air path switching valves that I can see in mine. I would assume the motor is pulse width modulated, but it could be a variable current design. In any case, either the motor had an issue that caused a reversal of direction and thus a reversal of air flow, or the control board had an issue. in either case, the cause is unknow, and in my opinion, the machine would need to earn my trust back.

[FirstNoele]

Bonjour, GWild, SuperSleeper, & Wrenchtwister1,

I'm grateful for all your support in this scary-freaky incident.  As soon as the single pressure machine arrives, I'll immediately switch to using it.  Even though this one hasn't repeated the trouble, I can never trust it again.

I agree with having a back up machine because I have a 96 AHI without a CPAP.  In 2009, when my ResMed S8 Elite II was still being paid for by the insurance company, I bought another one on [Commercial Link Removed]  CPAPAuction
It was brand new and included both manuals.  I wish I'd have kept it for situations like this.

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[FirstNoele]

Update:  The new fixed pressure CPAP is scheduled to be arriving today.  I'm relieved, because two days ago, I was woken up at 5:30 a.m. and gasping for air.  I ripped off my mask and the noise proved that the air was rushing out of the filter section of the machine, again. Not sure if an electrical "brown out" messed up the circuit board or something else.  At this point, I'm doubting that this auto CPAP can be a reliable back up for the new machine arriving today.

When it arrives, I probably won't worry about it being a used machine, like the one that the local clinician chose for me, last time.  Looks like I'll need to wipe out the DreamMapper app on my phone, so that the new machine can be recognized.  It'll be nice to have some worry-free sleep tonight.  Thanks for everyone's support.

[Hydrangea]

Do you have an OSCAR screenshot of this phenomenon?

[Gideon]

The only thing I can think of is that a couple of deals blew out on the assembly, one in the input side to allow blowing out the filter, and on on the output side to put the pressure in the case to blow out the filter.

[FirstNoele]

Hydrangea,

Thank you for your concern.  I sent the OSCAR upload to Bonjour last week.  He didn't see anything to demonstrate the surreal problem from last Wednesday evening.  Granted, all the repeated effort, from when it blew out into the filters, followed by stepping through all the settings, might have taken less than 5 min. but it felt like eternity. That incident would be just a flash on the report.

In any case, tonight is my first one with the new single-pressure DreamStation. 

[Crimson Nape]

Could you have a broken hose or hose connector? A break near the connector would feel like the air is coming out near the filter and it could act to siphon air at the mask.

[FirstNoele]

Chrimson Nape,

The hose to mask was a complete connection, and the hose to humidifier was also a complete connection.  

Now that I've received and installed my new CPAP, I can relax and enjoy a trouble free night's sleep.