Need help with CPAP for camper

[_DJ_1]

Fairly new to CPAP. The VA bought mine and it is strictly 110 volt. I thought no problem just get an inverter. Got a Schumacher 410 watt. Runs the CPAP OK but every time I take a breath in, the inverter runs then quits when I breathe out. The cooling fan on the inverter is noisy and very annoying since it does not run constantly.

I doubt if my VA Dr would write a prescription for a 12 volt model that I could go buy myself.

So, just wondering what others do. 12 volt machine or are there quiet inverters or put up with the noise?

Thanks.......DJ

[Empty_Nest__Soo]

A few thoughts on CPAP in an RV:

I’m not sure what brand you have, but in my experience anyone with an RV would do well to avoid ResMed CPAP’s. There are other choices that are far more suitable for use off of the grid.

You will use far less battery power by running off of 12 VDC rather than using an inverter for 120 VAC.

If you choose to use an inverter, it may need to be a pure sine wave inverter. Check the requirements for your specific CPAP.

Yes, you probably need the heated humidifier at home. But in an RV, you are in a small space with lots of humidity. You do not need to turn on the heat when using the humidifier, even in winter. Save some battery power.

If you want to buy a different CPAP for camping, you do not need a new script. The internet CPAP vendors will accept a script that you fax or email and it does not need to be a recent date. So long as it is written for you and shows your prescribed pressure, you can buy any kind/brand of CPAP you want. If you are paying, you do not need to settle for the cheapest most bare-bones CPAP that Medicare or your insurance insists upon. My script was for a regular CPAP, which I could not tolerate due to the constant high pressure, but with my script I was able to buy an auto-titrating CPAP which is vastly more pleasant to use. (It goes to the high pressure only on the rare occasions that it senses that I need the extra pressure.)

Another thing with internet sellers: The total price you pay may be lower than the co-pay on your insurance if you were to buy from a local brick-and-mortar medical supply. In addition, some insurance companies are happy to reimburse you for purchases made on-line – it saves them money compared to the brick-and-mortar suppliers. Check with your insurer.

Wayne

[PaulJ2]

I have a Respironics by Philips that is 12 volts with a "brick" for 120 volt operation. Just had to buy the optional 12v cord. Used for 3 nights with the humidifier function off, no problem with one battery.

[ktmrfs]

I suspect the problem is that the inverter is plugged into a 12V outlet and to much voltage drop. CPAP may need 10a or more peak, and that means putting the inverter either near the battery, or using 12ga wiring at least to the inverter.

trying to run my new resmed with a humidifier gave the same results you experienced until I beefed up the wiring to the 12V outlet I was using. Either trying to run it on the 24V converter for it, or a sine wave inverter.

BTW I've use CPAP for year in our trailer. What I have found is that even the ones that run on 12V will need a short and heavy gauge wire especially if the have the humidifier.

w/o the humidifier, wire isn't as big an issue, but likely will need a reasonably good connection to 12V.

And BTW ALL current CPAP internally are either 12V or 24V powered. they may have 120V going in, but that goes through a transformer to either 12V or 24.

And most of the current ones have an external brick that goes from 120 down to either 12V or 24V.

IF YOUR IS A RESMED S9 OR RESMED AIRSENSE S10 IT IS 24V INPUT!!!! NOT 12V. AND IS REVERSED POLARITY ON THE PLUG FROM COMMON PLUGS. YOU MUST USE THE PROPER CONVERTER FOR A DC INPUT. the ac adapter for the resmed is a 120V to 24VDC converter.

if it is a resmed, then battery power solutions offers a 12V to 24V converter that will power it and draw considerably less power than running it off an inverter.

HERE IS INFO ON RESMED CPAP

RESMED DEVICE WARNING: If you are using any device manufactured by ResMed you must use either a power converter or power inverter to complete the connection between the device and the C-100 Battery Pack as newer ResMed devices operate from a 24V direct current and the input plugs on older ResMed devices run opposite polarity from other manufacturer devices. DO NOT connect the Battery Pack directly to any ResMed model device as doing so will damage the ResMed device.

[j-d]

Had a ResMed S7. Called them about getting a 12-VDC adapter and they suggested just get a small inverter. I asked "Any Size? Any Type?" and they said 150-watt or so. Nothing about Sine or MSW. I bought a 400-watt Cobra MSW and it ran the thing fine, without humidifier.

EDIT: This was run on an oversized 12V battery in a truck camper. Probably equivalent to two ordinary 12V in parallel or two ordinary 6V golfcart batteries in series.

[we3]

~DJ~ wrote:
Fairly new to CPAP. The VA bought mine and it is strictly 110 volt. I thought no problem just get an inverter. Got a Schumacher 410 watt. Runs the CPAP OK but every time I take a breath in, the inverter runs then quits when I breathe out. The cooling fan on the inverter is noisy and very annoying since it does not run constantly.

I doubt if my VA Dr would write a prescription for a 12 volt model that I could go buy myself.

So, just wondering what others do. 12 volt machine or are there quiet inverters or put up with the noise?

Thanks.......DJ

I really.....really doubt that your cpap is strictly ac. With the extreme possibility of getting water from the humidifer into the fan motor it would be such a hazard they could not sell them. I have done this numerous times. I believe that if you look closely you will see that both the cpap and humidifier are both dc units. I could be wrong but I don't think I am. Oh, I just turn off the humidifier and run on a 400w inverter.

[Johno02]

What brand and model CPAP?? When I got my last one, I made sure that it would work on 12v. The previous one had a 12V input jack, and the newest one has a power block for 110v, and direct 12v input plug. I had a 12V power point installed beside the bed, fused especially for the CPAP. It runs overnight for several nights off two coach batteries.

Added on edit: My humidifier is attached to my CPAP. I fill it with water when parked, but turn it off. In my case, added humidity is not necessary so it works for me, but might not for others. Caution! always remove water before travel!

[tvman44]

I also recommend a Pure Sine Wave inverter, mounted as, close as possible to the battery. Medicare is a 5 year replacement cycle. 🙂

[Tiger4x4RV]

Get a DC cord specific to your machine if at all possible. This page has a whole bunch of different cords plus a phone number you can call if you have questions. They really helped me when I bought my cord. They will be able to tell you if your machine cannot run off 12V at all.

Before I got my 12V cord, I ran my CPAP for one night on my Duracell 100W inverter. Did not use the humidifier. It worked fine.

[Flapper]

Yep - another vote for a full sine wave converter. ALSO, look on the label on the back/bottom of the CPAP to find out the watts/amps it draws (watts = volts x amps). Info should also be in the full manual. Get an inverter at least 25% bigger than the CPAP needs. Also get a remote on/off switch for the inverter if you plan on mounting it somewhere harder to get to - inverters draw some power all the time they are on. Keep your 12v wires as thick and as short as you possibly can. It's OK to then run an extension cord from the 120v side to your CPAP.
I mounted my inverter in the baggage compartment, right next to the battery compartment. Then have a long extension cord snaked up into the TV area (which is primarily what we got it for). But the cord is long enough to get to the bedroom for my CPAP.
Haven't dry camped for long periods, but over 3 days, it didn't seem to shorten the battery life significantly from what I was getting before.

[1492]

Moved from Technology Corner

[time2roll]

+1 for getting a better inverter. I have and recommend Go Power sine wave.

[Larryect]

Using a true Sinewave inverter with the CPAP is highly recommended. The one you purchased isn't.

Placing the inverter near the battery source and running a 110v extension cord to the CPAP is more effective then running a long 12 volt line or using a 12 v outlet in the camper. Also, it gets the inverter out of the sleeping area.

If inverter or battery capacity is an issue, shutting off the heat on the humidifier helps a lot. You can still use water in the humidifier with no heat.

I think my HMO insurance approves replacements at 5 years. Or, if I think it is a problem and I really, really twist their arms......

[Pangaea_Ron]

I think that CPAP machines are on a 5 year replacement schedule. (Medicare)

I also have the $$$$ Respironics battery pack, although with my new CPAP machine the power cord has a different end fitting, which I discovered at a CG in Glacier NP during a snow storm. I needed to use my 1000 watt inverter for power, which worked fine.

[racer4]

I use a Respironics that runs on 120V or 12V.

I bought a battery pack from Powerstream. This allows me to run it straight from the battery pack. An optional $25 12V cord (made by Respironics) is required. This battery pack costs much less than those targeted towards CPAP use. Mine works fine. Get one with the bigger battery (20-22 AH).

It includes a 120V charger that I use to recharge the battery and runs from an inverter in the truck when driving around.

You might be able to get by with a larger inverter.

[Fishinghat]

I don't use the humidifier, so my experience is probably different. Also, my coach has an inverter that supplies 120 volt power from four house batteries, so that isn't an issue. The battery backup system from the manufacturer was something over $300.

At home I made a battery backup in case the power went out, especially at night when I probably wouldn't be aware of it. I used a tractor battery from Costco, about $65, and an automatic 3 amp battery tender supplying the battery with replacement power. I leave it connected all the time.

I'm on my third CPAP machine and all of them worked on 12 volt power, abet with a transformer in the power line to drop voltage from 120 to 12. So, I just bought a power plug from an electronics store (negative on the outside, positive on the inside) and wired it up.

I'm not sure what the replacement schedule is for CPAP machines as I could never get a straight answer from anybody. But, I found if I complained that my machine wasn't working like I thought it should, it got replaced. All of my machines have had a recording device built in and the results could be downloaded by the provider.