CPAP Machine Useage

[centennialman]

I use a Resmed S10 CPAP machine and bought the battery back up unit to use when boondocking. I will use it for the first time this summer and will report back on the results.

[NoNameinNM]

Our battery packs have performed flawlessly. My husband and I have different Resmed machines, so our packs are configured slightly differently, with the appropriate converter, etc.

There are two things of which one must be mindful. First, my husband and I both have two batteries and they can take several hours to recharge if they are largely drained. Second, they don't hold a full charge for a great length of time in storage, so it's definitely important to check them before a trip.

When boondocking for more than a few days, a generator or small solar panel system would be an excellent idea. I've used CPAP machines for 20 years, and in the early days when we still camped in tents, my husband kept my CPAP machine running with a solar panel, inverter, and deep cycle RV/marine battery.

[wdcgator]

I solved my CPAP problem.. I went to Harbor Freight and bought one of those racks that go on the back of your car and slides into the trailer hitch. I sawed off the trailer hitch part. I then moved my butane tanks forward 4 inches and the rack fits perfectly behind the tanks. Screws and U Bolts. I then bought the ultra quiet Predator 3500 watt generator for $750 fits right on that rack beside the battery. I also installed two batteries on the same rack..A 5 gallon gas jug will also fit.

[Gearheart]

I use the ResMed 9. When boondocking I do not run the humudifier. A 400 watt inverter is adequate to run through the night. I have 2 group 24 AGM batteries. On a sunny day I am back up to full charge before noon (160 watt solar array).

[swakyaby]

I know this is an old thread, but was wondering if CPAP users have current recommendations for boondocking and CPAP users. I use the Resmed Airsense 10 CPAP that requires 24V and 90 watts. We don’t have a generator and would like to avoid getting one. I have seen the Freedom battery packs for the ResMed Air10: 1 battery only lasts 1.5 nights with humidifier and heat turned off ($329.95), and the 2 battery pack lasts 2-3 nights($539.90). The 2-battery pack option sounds like it would be okay for a weekend. My question is, is $540 the best option currently for a mostly weekend boondocking Airstreamer? Anyone see better options price wise that don’t require AC power and generators? Thank you for your thoughts.

[DKB_SATX]

Originally Posted by swakyaby

I know this is an old thread, but was wondering if CPAP users have current recommendations for boondocking and CPAP users. I use the Resmed Airsense 10 CPAP that requires 24V and 90 watts. We don’t have a generator and would like to avoid getting one. I have seen the Freedom battery packs for the ResMed Air10: 1 battery only lasts 1.5 nights with humidifier and heat turned off ($329.95), and the 2 battery pack lasts 2-3 nights($539.90). The 2-battery pack option sounds like it would be okay for a weekend. My question is, is $540 the best option currently for a mostly weekend boondocking Airstreamer? Anyone see better options price wise that don’t require AC power and generators? Thank you for your thoughts.

I have the same CPAP machine. I had an S8 Compact before that ran on 120v, and I didn't question the machine my insurance company replaced it with when the 7-yr-old S8 couldn't maintain pressure anymore... I knew it was DC in but didn't realize it's 24V!

I think the "Freedom" battery packs are a terrible deal. I'm not TOO sure about the $85 DC-DC power supply from Resmed, but if it destroys my machine they can hardly complain about it being my fault, so I may get one of those rather than just putting 2 small AGMs in series which was my first thought.

I'll probably wire a 12V socket by the bed and try the trailer batteries first. I can run it overnight off the inverter and get the batteries charged back up with my 160w portable solar on a sunny day, but the cheapo inverter isn't particularly efficient so I think it would work better with the ResMed power supply running directly off DC.

The 90W, by the way, it at max pressure with the humidifier running full tilt. Most users who've measured report about half that... I should dig up my Kill-a-watt and see what mine actually pulls on a normal night. For the old S8 I just went by the specs and bought an efficient inverter and an overkill battery... I thought I'd be doing well to get 10 hrs out of it, it would run more like 24! I didn't have an inverter built into that trailer.

[swakyaby]

Originally Posted by DKB_SATX

I have the same CPAP machine. . .

I think the "Freedom" battery packs are a terrible deal. . .


I'll probably wire a 12V socket by the bed and try the trailer batteries first . . .

I was thinking that those prices on the Freedom batteries were really high, thanks for confirming I’m not the only one. Seeking out other options before resigning myself to those kind of prices. I didn’t think installing a 12V socket would work with this CPAP as it requires 24V.

[DKB_SATX]

Originally Posted by swakyaby

I was thinking that those prices on the Freedom batteries were really high, thanks for confirming I’m not the only one. Seeking out other options before resigning myself to those kind of prices. I didn’t think installing a 12V socket would work with this CPAP as it requires 24V.

ResMed sells for $85 a 12V-input DC to DC converter that runs the output up to 24V for their machines. It's 1/3 the price of a single "freedom" battery pack and lets you use any 12V source, even a big honking AGM on the floor (it has both a 12v plug and alligator clips.) Actually I think the "freedom" battery packs may just output 12v and still require the DC to DC converter!

This is a cheaper knockoff but its input is just for that company's batteries... It could easily be modified but might be just as good to buy the more-expensive ResMed one with better connectors.

[swakyaby]

Thanks for the info, David. This has been helpful.

[68 Overlander]

Originally Posted by DKB_SATX

I have the same CPAP machine. I had an S8 Compact before that ran on 120v, and I didn't question the machine my insurance company replaced it with when the 7-yr-old S8 couldn't maintain pressure anymore... I knew it was DC in but didn't realize it's 24V!

I think the "Freedom" battery packs are a terrible deal. I'm not TOO sure about the $85 DC-DC power supply from Resmed, but if it destroys my machine they can hardly complain about it being my fault, so I may get one of those rather than just putting 2 small AGMs in series which was my first thought.

I'll probably wire a 12V socket by the bed and try the trailer batteries first. I can run it overnight off the inverter and get the batteries charged back up with my 160w portable solar on a sunny day, but the cheapo inverter isn't particularly efficient so I think it would work better with the ResMed power supply running directly off DC.

The 90W, by the way, it at max pressure with the humidifier running full tilt. Most users who've measured report about half that... I should dig up my Kill-a-watt and see what mine actually pulls on a normal night. For the old S8 I just went by the specs and bought an efficient inverter and an overkill battery... I thought I'd be doing well to get 10 hrs out of it, it would run more like 24! I didn't have an inverter built into that trailer.

We are going to stock the new EXP 380 Pro and you can use them up to 3 nights before charge. Solar charging even available for boondockers. 3 USB ports, just a great machine as far as I can tell. I don't bite many lures but this has real features and nothing on the market in the class comes close. I'll let you guys determine if I'm right. 144 watt hours. 2-3 nights of power.

[nryn]

I used to travel a lot and currently use a Philips Respironics DreamStation Go with the battery. I used it earlier this year on a camping trip, charging the battery via an inverter while driving. It worked great. I like it a lot better than the Z1 I had (with battery), though it is about twice the size.

Unlike my machine at home, the Go doesn’t have a humidifier (yet) but so far that hasn’t been an issue.

[Lewis774]

Check her AHI scale, she may be able to have a dental apnea appliance if she has mild apnea. Would not use any power.

[Julie-Bob]

When off the grid I use my Honda 2000 in the bed of the truck and have modified the cap on the Honda to run from a 5 gal can in the truck bed and it has ran for more than 36 hrs straight this way. So in the morning I can make coffee without getting out of the trailer.

[wdcgator]

The 16 hour Lofta Air Mini is small compact ac or battery.

[DaveP]

My wife and I both use a Philips Respironics DreamStation. We got the 12 volts adapter cables and I installed a cigarette lighter outlet between the beds. We use the humidifiers and it runs all night drawing very little of our total battery power.

[spatters]

Hi Folks,

I use a Resmed S10 with all the bells and whistles and a full-face mask that ramps up to max pressure over the course of a night. I use my CPAP every night, everywhere in the world. I haven't missed a night in 15 years and didn't intend to start when we got the Airstream.

We did a 3 week trip cross country (from W to E) over January. We stayed in state parks, campgrounds, parking lots, everywhere. Our longest dry camp was 4 nights.

We have a 2018 International 30' with upgraded batteries (not lithium) and 400W of solar on the roof. Winter camping so the solar wasn't super awesome imho.

To ensure CPAP use I bought the 12v adaptor for my machine, two freedom batteries with necessary adaptors, and two Honda 2000 generators that run off propane. Overkill. However, it did give me the opportunity to explore multiple solutions.

When we are at full hook-ups (50AMP or 30AMP) I plug the CPAP into an AC outlet at the bedside and use full therapy as usual. No problems. Just like home with the exception that I had a couple of rainouts due to high humidity but got that solved with some tweaks to the heated tube and a tube wrap.

For a single night of dry camping I was able to run the CPAP full-out using the 12v adaptor without draining the AS batteries below what seemed to be a good charge. However, it did pull a lot of charge from the batteries. The charge jumped up just fine after sun-up when the solar started to do it's thing. I don't think I would do this without upgraded batteries. On another night I disabled the humidifier (went passive, still had water in the tank, just no heat) and disabled the heated hose. This also worked fine and drew less from the AS batteries but it still seemed to pull a lot given that I had turned-off the largest power hogs on the machine.

Using two freedom batteries in tandem I was able to run the machine only (no bells and whistles) all night. Plenty of charge left in the AM. I also tried the heated humidifier and no other stuff and had charge left in the freedom batteries in the AM. When I ran the machine full-out on the freedom batteries, they both drained to zero before the end of the night.

We only used the generators when dry-camping to bump up our battery charge. We never ran them all night to enable CPAP. So the generators were surely the emergency back-up plan.

How I plan to manage in the future:

hook-ups = normal use
1 night dry-camp = 12v AS power, no humidifier, no heated hose
multi-night camp = double freedom batteries recharged from the generator or via the trailer inverter (if there is sun for the solar) during the day.

We're doing 10 weeks over summer so I'll test more there. I might play with the amount of humidity or temperature of the hose to see if I can tweak the power drain without going to an all or nothing position.

If I were doing this without investing a ton of money I would acquire CPAP modification gear in the following order and see how each worked for your unique therapy:

12v adaptor
Freedom batteries
generator.

If you need the generator for other reasons you might change the order I suppose.

My $0.02

spatters

[centennialman]

Thanks for the information Spatters.

I have the exact same machine and find that the Freedom batteries don't make it through the night. I do the same as you and use the machine, full out, when plugged into 30A.

I have solar and can recharge the batteries during the day. Haven't bought a small generator to take with me yet. May have to do that as I plan more boondocking in the future.

[daleyocum]

For those with 24v machines who are handy enough to hook up a few wires, Amazon is full of 12v to 24v converters. Here's an example.

[dlykken]

I have a 2019 Globetrotter & us a CPAP & have not had an issue going through the night. I have solar to charge in daylight & 2 Honda 2200 generators as a backup, if we need them, but rarely do need them.

Another option I have & recommend that will run your wife’s CPAP several days without using your Airstream batteries is a ”GOAL ZERO YETI 400 stand alone battery” which by itself will run the CPAP a couple days. Here is a link https://www.bhphotovideo.com/c/produ...generator.html

B&H puts them on sale & I think I paid $399 for mine. It powers laptops, iPhones, CPAP & it has the option to charge with a solar panel during the day. It is a great option to look sat.

[rickst29]

Originally Posted by daleyocum

For those with 24v machines who are handy enough to hook up a few wires, Amazon is full of 12v to 24v converters. Here's an example.

Resmed (model S9 and model S10, and maybe some others) uses a 3-wire adapter. (Ground Outside, +24VDC on the inner shell, and a funky pin in the middle. That center pin must be built with a 3.3V power supply, followed by a 2.7k Ohm Resistor.

The Resmed CPAP machines perform a "sweep" on that connector, effectively verifying both the supply voltage and the resistance. In their patent, they describe that different resistors may be used to indicate different power supply capabilities (60W versus 90W and etc.).
- - - -
If you want to know all the gory details which go into building a "Resmed 12V" converter of your own, you can look at the one I built for my wife. In comparison to the $85 Resmed, I saved money and used higher quality parts - but I turned around and spent the small "savings" on a high-amperage twist-lock connector pair (plug and socket), to keep it from getting pulled out of a Trailer 12V "cigarette plug" adapter during the night. Here: http://www.cpaptalk.com/viewtopic/t1...rsense-10.html