CPAP help

[ilanortho]

Hi;

Have a CPAP that draws 4A at 120V . If I buy an inverter that translates to roughly 40 A at 12 volts. The invertor though has to be hooked up to the battery and it would require a 10 foot run of 10 Ga wire. Besides putting a permanent setup on my boat, it would be a real pain to lug all this junk on flights etc. Anybody have a better solution?

Thanks.

Ilan

[Allan S]

I am in your shoes. We have been cruising for 4 years now and I got a new machine before we left. Asked for a battery or a 12 volt machine but was told they didn't exist.They lied through their teeth. The machine eats power.The inverter eats power. We are power misers on this boat and I regret not shopping around prior. Good luck.

[tenchiki]

I just recently got a CPAP. The power brick puts out 24V (which a 12v->24v DC-DC converter might work more efficiently). I was told (and believe but haven't verified it myself yet) that the major power consumer is the humidifier, which you should turn off when on a boat, as there should be sufficient humidity afloat.


Also, mine doesn't draw anywhere near 4A@120v, in fact the power brick is rated to deliver a max of 3.75A@24V. I would double-check your power consumption.


I could probably save a bunch of power getting a less-automated one, too.

[Singularity]

There doesn't seem to be any solution other than to comparison shop for units that require less DC power and to buy appropriate cable. Avoid going through the inverter.

Also try to buy a machine that has some form of user monitoring capability (a "smart" device, not a "brick" unit). I'm not familiar with the newer bluetooth w/app units, but the devices that store on an SD card can be used with a computer with free sleepyhead software (found here, demonstrated here) to monitor treatment to a very high degree (with a little time/experience).

[fritzdfk]

Don't use humidifier or heated hose.

[Dsanduril]

Look around/talk with your doctor about a “travel CPAP”. We had a guest last season who had unit with a 100Wh battery that lasted ~9 hours each night (20cm pressure). No humidifier, used exhaled moisture to humidify inspired air. Sorry, don’t know the brand. We just re-charged the battery each day, but for longer term use I’m sure you could sort out connection to the house bank.

[Marinarius]

That must be one honkin' CPAP, it draws more than double the power of the most common units.

[mickt243]

I have a resmed “airsense10” - the power brick that plugs into the wall is rated at 90 watts....
It also came with a “travel adaptor” that had big alligator clips to connect to a car battery - also rated at 90 watts... without the humidifier and heated tube (as mentioned by others) it draws less than an amp@12v
I recently got the proper battery kit from them - rated at 90 watt hours. With the humidifier and heated tube on, it lasts 2-3 hours, off, it lasts 10 hours plus...

[Island Time O25]

Phillips has a 12v model. Its brick converts to from 120v to 12v. Can be used directly with a regular 12v plug (at least 3A fuse but 5A would be better) without any issues. That would be the best solution. Just make sure your 12v wiring at the socket can handle 5A draw.

Also Resmed has a battery travel pack. It's a bit pricey at $300 but it's good for 2 nights and takes about 8 hours to recharge. Since it is not used during the day my guess would be it can probably charged by a solar hook up.

FWIW, resmed with humidifier and heater draws 5A but without these only 3A. Why would you need a humidifier on a boat?

[Bazz]

I have two CPAP, one Fisher-Paykel stays at home and has a humidifier with a heated hose, the other is for traveling: a Transcend model, something like this but an older model. I have two batteries that can do 2 nights each and they can be charged on a 12V outlet, or any other AC outlet. I also have a solar panels charger for those batteries and a small portable inverter that I can plug on AC to recharge - I use it either to recharge the batteries or drive the CPAP directly. In seven years, I have not been more than 5 nights without a CPAP. I carried the Transcend everywhere, Central america, Europe, Africa, camping, trekking, etc. No heated hose, no humidifier. I have the humidifier add-on for it, but never used it. It's more a backup plan if the one at home fails. Yes, nose may dry up a bit if you are in a electricity heated motel on a cold and windy night - that's the price to pay. I hear they now have small add-on devices that will recycle water from your breath to humidify incoming air. As for sailing, you really don't need a humidifier of any sort, but you may have to let go accumulated water in the tube once a night if air temperature is a bit cold. I really suggest having two CPAP. The bedside models seem to not travel well, too bulky, too heavy, too fragile. I had one that died and was told that this was the reason. Costly to replace, more than a Transcend.

[Belezar]

Look on CPAP.com. There are several options, at least one can use a 12v connection

[ilanortho]

Thanks. Ilan

[Adelie]

I measured the total draw of my CPAP at home, it was like 150-190 W-hr per 7hr night with the humidifier on.