Repairing a sleep apnea device?

[imseeker]

I have a Series M Auto bi-pap. Has worked great till about six weeks ago.

Now it power cycles, then gives up and says "service required". Since it is 8 years old, no one seems to want to touch it.

Get a new one. Ok, I am, but I've lived six weeks without one at all. I would love to get this fixed so I have a backup.

I can even get it to work occasionally, if I hit random buttons and get it to start up, so the issue is not in the mechanics, it is in the "will the machine allow itself to work".

Any thoughts on how to get an item repaired? Or make this work?

I took it to the people who are providing me a new machine, but sure enough, it worked for them! Then I get it home and we're back to power cycles.

[retired_guy]

Sounds like the power brick to me IM. When you took it to the provider, did they use your power brick or their own? Not that it matters much.

But could be a simple replacement of the power brick might solve it.

[trish6hundred]

Hi imseeker,
WELCOME! to the forum.!
It sounds like you are having trouble with the power brick for your machine.
Hang in there for more suggestions, I hope you get your machine working and best of luck to you as you continue your CPAP therapy..

[archangle]

I'm sort of stabbing in the dark, but here are some suggestions.

First, take out the water tank so you don't spill water in the machine.

That doesn't really sound like a power supply issue, but it's possible.

Remove the blower unit from the humidifier and work with the blower unit by itself.

Wiggle the power cord and other connections.

Try a different electrical outlet.

Measure the voltage of the power in your house.

See if you can find a different cord to go from the power brick to the wall. The one on your new machine might fit.

See if setting the blower unit on its side, upside down, etc. makes any difference.

If you use the blower without the humidifier, you need a little hose adapter that should have come with it to begin with, but most people lose it. I think Supplier #1 stocks it for around $10.

You can buy a replacement power supply online, but they're $90 or so. I'm not that confident that's the problem.

[imseeker]

Thanks for the replies. They used my power brick, and for THEM everything worked fine. In fact it worked "initially" when I took it home, then I probably pressed some button that put it into a different mode and boom, power cycles, "service needed".

Power SEEMS fine, but I get the concept that the brick is the issue.

The health company person said it was the interface between the humidifier and the unit, because she separated them, and it worked immediately (she never saw the power cycle issue at all). So we all tend to point to what we see. I get that. But when I took it home, the humidifier was attached to the unit, and yes, that worked too.

Diagnosis is tough.

Oh - here's more - I'm concerned that a voltage line regulation may have caused it. I had a WONDERFUL time staying in an Earthship in Taos, NM - but that's the night things began. They generate their own electricity, and I'm wondering if their line voltage was "off". Maybe it burned out the brick. Maybe it burned out a card? But the next night I had problems, but finally got it to work - just pressing buttons. Since then - it's been non-responsive (vs. just power cycling and saying service needed).

The kicker is it worked like a champ at the health service provider and when I got home - again until I pushed some buttons.

[retired_guy]

It might work at home again if you unplug it and let it sit around for an hour or so. Until it doesn't work again. The power supplies seem stupidly simple, but if they are putting out a bit brown, then your machine might be cranky.

It's probably worth borrowing a power supply from your supplier for a day or so just to test it out.

[justMongo]

Thanks for the replies. They used my power brick, and for THEM everything worked fine. In fact it worked "initially" when I took it home, then I probably pressed some button that put it into a different mode and boom, power cycles, "service needed".

Power SEEMS fine, but I get the concept that the brick is the issue.

The health company person said it was the interface between the humidifier and the unit, because she separated them, and it worked immediately (she never saw the power cycle issue at all). So we all tend to point to what we see. I get that. But when I took it home, the humidifier was attached to the unit, and yes, that worked too.

Diagnosis is tough.

Oh - here's more - I'm concerned that a voltage line regulation may have caused it. I had a WONDERFUL time staying in an Earthship in Taos, NM - but that's the night things began. They generate their own electricity, and I'm wondering if their line voltage was "off". Maybe it burned out the brick. Maybe it burned out a card? But the next night I had problems, but finally got it to work - just pressing buttons. Since then - it's been non-responsive (vs. just power cycling and saying service needed).

The kicker is it worked like a champ at the health service provider and when I got home - again until I pushed some buttons.

Some generators have terrible outputs that the switching power supplies in/for CPAPs have problems with. So, it could be the power supply.
The generator is Taos may be out of spec for US voltage; but most CPAP supplies are designed for world wide Voltage and frequency. It's the purity of the sine wave; and transient spikes that are the issue.

It's interesting that it works when separated from the humidifier. The humidifier is a big power load (typically bigger than the blower unit.) Again this tends to point to the power unit.

BTW -- Taos is near the maximum altitude that a CPAP is spec'ed to operate. (2124 meters vs spec of 2591 meters)

[TorontoCPAPguy]

If it is a power supply issue, and I am not suggesting it is, the first thing I would do is try another power supply right? If that works you know what your solution is and if you are a tekky like the rest of us radio amateurs around here you should be able to cut the cord coming out of the power brick and attach it to some cheap generic brick to provide the necessary voltage and sufficient current to the blower. First thing I might do is simply remove the humidifier if that is possible on your machine. The humidifier general gobbles up a great amount of power (current) and without the humidifier gobbling that current and stressing the power supply you may find that it works fine. To be safe though, I think I'd check the blower out on another power supply and if it works on that power supply, replace yours with an OEM power supply or a generic power supply with the proper cord on it.

[imseeker]

I'd love to test the power supply - but I'm trying to find one that works. This one has a red inner lining (and I think the colors do mean something). Don't have any that fit. Maybe I'll have to buy one, even if just to test.

[Galactus]

Always the option of testing the supply with a meter. Though it may only fail under load, or after a period of usage, but it's always worth a try to just check it.