Inverter for Fans and CPAP?

[MTHome]

Help a piano teacher and demo architect out here. My husband and I are often on the road for weeks at a time. We would like to be able to do 2 things. 1. Run a fan in the TT when stopped during the day for my husband's work calls. 2. Be able to boondock in Montana this summer. My husband has a cpap that isn't optional. For his healthy and to keep me out of jail 🙂

What do you recommend as far as being able to accomplish these two goals? We just bought a new 2015 North Trail NT 26LRSS by Heartland. I'm super excited about the new rig. It's an upgrade from our first one that we got last year. That was a 2008 Passport Ultra Light. It's small enough I can still take it out alone to sheep and wool festivals, but big enough for us to full-time while we build a house next year.

Thanks!

[SoundGuy]

Chandalen wrote:
Inverters. I have yet to see an inverter at Walmart type stores that I consider 'safe' to use. They are almost always modified sine, or worse yet modified square inverters.

The reason given before was kinda incorrect as to why they are bad.

In layman's terms, there's nothing "kinda incorrect" about saying (as I did earlier) that a 120 vac fan motor designed to run on a sine wave signal will either not run at all on modified sine wave or if it does will make an annoying racket.

[Chandalen]

You should always use a device on the 12v system if possible. You lose power converting to 110, then back to 12v or 15v whatever the item is wanting.

Inverters. I have yet to see an inverter at Walmart type stores that I consider 'safe' to use. They are almost always modified sine, or worse yet modified square inverters.

The reason given before was kinda incorrect as to why they are bad. A Sine wave has a limited fixed time at the 0 state. Most expensive electronics are counting on this fixed time 0 state. Its how some clocks keep time, thats how fixed it is.

What happens with a modified sine wave is that 0 state is a variable length and longer than it should be. This makes them inefficient and provides voltages other than what the device is expecting. Mac's (if they turn on) will fry their power packs very rapidly on a modified sine.

Its worth the added cost for a TruSine Inverter! The CPAP is loud enough, why make it louder!

[BozemanTrail]

Before going to 12v DC for the CPAP, look up info about the specific model being used. For example, for resmed units, google "resmed battery guide" and you'll find a nice guide to batteries for some resmed models. Now, the interesting thing is that you will notice that a lot of models don't run straight 12v and you'll need a DC/DC converter anyway. You'll also notice that some units are more efficient using an inverter (AC/DC) than a converter (DC/DC) so you'll save more battery with an inverter.

[MTHome]

Thanks for all the suggestions! I'm going to pass this on to my husband and let him decide what'll work best for him.

[C_Schomer]

I have an older bipap that Takes 12vdc directly w/o an adaptor that I keep just for the RV. Check the mfgr of yours and see if they have an adaptor. I put 150watts of solar and two 6v batteries on our previous RV and that was enough to keep us in 12v for my bipap, lights and some vent fan use. The first owner of our current 5er put on 240 watts and two 6 v batteries and three of the big vent fans and we can run whatever we want w/o worrying about running low for the bipap at night. Craig

[beemerphile1]

We use two fans, an Endless Breeze and an 02Cool. Both run on 12vdc.

We also run the CPAP on 12vdc with the appropriate cord.

An inverter adds extra complexity, expense, and is less efficient.

[SoundGuy]

MTHome wrote:
1. Run a fan in the TT when stopped during the day for my husband's work calls.

While a $10 120 vac fan from WallyWorld may circulate the air just fine chances are if you try to run it using a MSW (modified sine wave) inverter it will either not work at all or if it does will squeal annoyingly, the reason being that fan motor was designed to run on a sine wave signal. The solution is easy, but costly - a pure sine wave inverter. Considering this, you'd be better off with a fan such as the Endless Breeze which is designed to run directly on 12 vdc and ignore the inverter entirely. I've never used a CPAP machine but it seems to me your best choice would to also use one that will run directly on 12 vdc and again, ignore using an inverter.

[scrubjaysnest]

I understand there are CPAP's that use LiFePo batteries and they get a week between recharges.
As for inverters; Morningstar has a very nice 300 watt but does have a price tag also.
Fans we use the fantastic vent fan, 1 amp on slow setting, and O2 Cool portable 12 volt fans. Wally world sells the O2 Cool under the Ozark Trails brand name of camping gear. Also available at Gander mountain.
We dry camp 90% of our camping.

[GMandJM]

cmoecmoe wrote:
I have also tent camped with my CPAP by using a automotive jump box ...

Craig

I wondered if that could be done. Will mention it to my Aunt who uses a CPAP. Thanks for the info.

[time2roll]

I recommend a 12 volt fan. Possibly a 12v adapter for the CPAP but I think you may as well get a small 300 watt inverter to also charge small items and run a tv/dvd.

+1 for 200+ watts of solar if you will be off-grid for extended periods.

[pianotuna]

Welcome to the forums.

Start with an energy audit.

If you plan on boondocking with no shore power then consider adding a solar system.

[BTPO1]

Tiger4x4RV wrote:
Often, you can purchase an optional 12V cord matched to your CPAP unit and run the CPAP on 12V. That is what I do. More efficient than an inverter.

As to fans, Fantastic Fan (usually overhead vent) runs on 12V. FF also makes Endless Breeze fans, with 12V cord; these are portable to the length of the cord.

X2, cords are much cheaper than an inverter. JMO

[cmoecmoe]

I have also tent camped with my CPAP by using a automotive jump box and a cigarette plug adapter for the unit. You can then make a double ended cigarette plug and plug it into the engine side of the coach or TV to charge when driving.

Craig

[Dakota98]

Boondocking & CPAP.

Yes, run the CPAP & or humidifier directly from any 12 volt outlet directly, no inverter, when shore power is not available.

I would also suggest a small generator or 100 watt minimum solar install to keep the batteries charged & not let them get below 50% SOC.

Check your converter & determine if it has a 3-4 stage built in charging system. I doubt it does, but that would be beneficial to maintaining a good charging profile for the batteries in conjunction with shore power or the generator

I personally run my CPAP from a dedicated 35amp 12 volt AGM battery, so not to use the coach 12 volt system, recharging it as needed.