PB Goodknight 420G not working at high altitude

[dougjgreen]

I´ve got a big problem. I am currently on vacation in Cusco, Peru, at an altitude of just over 11000 feet. My PB Goodknight 420G is not functioning properly due to the altitude. When it´s blowing air, it seems to be blowing a noticeably lower pressure than normal, even though the readout says 15.0

Also, it is constantly shutting itself off because it detects leaks, even when there are no leaks - undoubtedly due to the low air pressure at this high altitude is fooling the pressure sensor. I could probably get by with the lower pressure, but the constant - literally every 10-15 second shutoffs are making it impossible to use this machine - and I don´t expect that I can pick up another one here in Peru on short notice.

Is there any way to program this machine so that it keeps blowing even when it detects leaks and low pressure? And what can I do about this, I will be here for 6 more days and I am already getting sleepy from my CPAP not working. I REALLY can´t function without CPAP for more than a day or two tops.

[Snoredog]

The 420G has Auto-Altitude adjustment. However, most machines are only designed to work up to about 9,000 feet, so if it works at all at 11,000 feet I'd be surprised. Got a pulse oximeter?

The machine has to have that smaller pressure-feedback hose connected so it can sense what pressure delivery is. If it cannot sense that back feed pressure coming from the large hose it will shut off.

Sorry, but there is no other adjustments you can make to make it work other than bumping up the pressure to compensate but that would only serve to exacerbate the problem.

[dougjgreen]

No, I don´t have a pulse-ox meter here in Peru. And I found the manual to the 420G online, and it says that the device is spec´d to work up to altitudes of 7800 feet. I´m 3400 feet higher than that right now, and will be for 6 more days, and really not sure what the hell to do.

[Bearded_One]

The 420 series CPAPs are not very powerful CPAPs. Increasing the pressure setting isn't likely to increase the pressure that it is putting out.

You might want to try is to power it from a fully charged battery rather than from the wall wart that comes with it. The voltage from a fully charged battery is a volt or two higher than the rated voltage of the wall wart, which might help some. It is also possible that the wall wart isn't putting out a full 12 volts with the higher power load caused by the higher altitude. It is safe to power it at 14 volts.

[plr66]

Can you get yourself to Agua Caliente (Macchu Piccu) right away instead of staying in Cuzco for 6 days? The altitude is around 8000 feet. Still not within the range given for your machine, but possible a fix.....and what a great place to be for that many days! I found no trouble finding a room when I was there, though you need to ask one of the local tour companies to locate that for you before you catch the train. I sure do feel for you and wish you the best with sorting out what to do.

[Snoredog]

No, I don´t have a pulse-ox meter here in Peru. And I found the manual to the 420G online, and it says that the device is spec´d to work up to altitudes of 7800 feet. I´m 3400 feet higher than that right now, and will be for 6 more days, and really not sure what the hell to do.

that's what I meant by the Pulse Oximeter, at least you could monitor your SA02 levels. Nonin makes the sport model pulse oximeter for that very thing, for people that climb and fly at high altitudes. If you had one of those Pure-Sleep snoring devices that might help but doesn't do you much good from there now.

[dougjgreen]

Well, an update - the machine seems to work intermittently, and as a result, I sleep intermittently. Over the course of 10 hours, I got two slices of 2.5 to 3.5 hours or real sleep, and I felt fairly rested, but not deeply rested this morning.

Unfortunately, I´ll only be in Aguas Calientes for 1 of the next 5 nights.

[ozij]

Raise the pressure, and make sure all your electric cables are connectef firmly on both sides.

O.

[dougjgreen]

It´s not the cables - what I meant by working intermittently was how aggressively and frequently the leak detection sensor is shutting off the pressure. There have been a couple of sessions of a few hours where it didn´t do that much, and I could sleep. And my pressure is already set to 15.

[greyhound]

I, along with my 420G travel CPAP, just returned from Peru yesterday. In addition to being in Cusco, I was in Puno (Lake Titicaca) which is about 12,500 feet and, fortunately, didn't experience any problems similar to yours. Is there any chance your hotel's electricity is having power problems?