Community Forums

calguy42 · 08-06-2014, 09:13 AM

1st actual post. We have a 2002 Jayco Grey Hawk and my wife uses a c-pap when she sleeps. The coach has 1 12volt battery. If we are dry camping, will the battery hold its charge all night?

homeless · 08-06-2014, 09:15 AM

If you hook it directly to the 12 volt rather than running it thou an inverter it will last longer.

**pasdad1** · 08-06-2014, 09:24 AM

Don't expect to run a heated humidifier option(if available) on the CPAP...the heat takes much more power.

Should work okay without the heat.....and running direct from 12v as already suggested.

Adding 100 watts of solar would charge the battery every day for free, if you intend to boondock very often.

BFlinn181 · 08-06-2014, 09:43 AM

If you have room, install a second battery. You could even use a portable 'jump start' battery to power the c-pap.

A unit like this:
3-in-1 Jump Starter and Power Supply

can be recharged by 120v or a double-ended 12v charge cord from your alternator.

Skip426 · 08-06-2014, 09:45 AM

As other members have indicated, direct hook up & no humidifier will help.
Battery condition and size are factors, not all batteries are created equal, other loads in a dry camping situation , fridge uses power for control panel and propane control.
If your in a situation where you have to run the furnace , the battery probably won't last through the night , and as the battery state of charge gets lower , it takes longer to recharge, so without proper charging if your dry camping for an extended period you may have power issues on the second or third night.
JMHO. I'd look for a way to install a second battery , and maybe dedicate it to the pump.
EDIT: I see Bob , posted the same info while I was typing, boy I type slow.

h2oviller · 08-06-2014, 11:18 AM

I will share my experience and maybe it will help you. My wife uses a CPAP w/humidifier. Our motor home had 2 12volt house batteries which were only rated at 55 amp hours each. The first time she used her CPAP, when we were dry camping, the house batteries were pulled down so far that the generator would not turn over. Switched those batteries out for 2 6volt Costco golf cart batteries rated at 220 amp hours each. What a difference! In the morning, the 6volt batteries have plenty of juice left. I also added a 12v power point in the base of the bed for plugging the unit into. A very positive improvement!

wa8yxm · 08-06-2014, 01:15 PM

There are many factors .. I would have a 2nd Charged battery handy the first night.. Then, wire it in even if you do not need it.
Some battery facts:

ON a true deep cycle battery you can safely use 1/2 of the power it holds. So if the battery is a 100 amp hour. you can use 50.

ON marine/Deep cycle, I would recommend closer to 25 percent max use (25 amp hours)

The common GC-2 Six volt battery (2 in series make a big 12 volt battery) run 210-250 amp hours, use 220 as your guide as that is most common.

A single Group 24, by comparision, fits the same tray and holds only 75 am hours (THe GC-2 and the Group 24 are very close in width and depth, The GC-2 is a bit taller)

Group 27 is just under 100 amp hours
Group 29 just over.. Use 100 for both if you are estimating

A group 31 is 130 amp hours.

calguy42 · 08-06-2014, 04:59 PM

Thanks for the all suggestions. I may look in to the 2 golf cart batteries. I have read on other posts about doing this. When I said dry camping I should have clarified it a little bit. It would only be for one night on the road (such as stopping at a Wal-Mart parking lot) and the next night in a campground.

**pasdad1** · 08-06-2014, 05:16 PM

Quote:

Originally Posted by calguy42

Thanks for the all suggestions. I may look in to the 2 golf cart batteries. I have read on other posts about doing this. When I said dry camping I should have clarified it a little bit. It would only be for one night on the road (such as stopping at a Wal-Mart parking lot) and the next night in a campground.

Then you're fine with your one battery (provided its in good shape).

Ron_H · 08-07-2014, 08:17 AM

Before you buy anything verify what your wife's CPAP runs on. Not all are 12v.

Another option to consider is the age of her current CPAP and the frequency of your travel. One possible option is to purchase a second "travel" CPAP.

Prior to retiring I travelled a good deal and purchased a second CPAP to use for travel as well as a backup in case mine failed. There are a couple of small and light units that are compatible with portable battery solutions that work very well for this.

I have a EZEX Travel by Transcend that I've used for travel for the past a few years and simply plug it into my coach and let the inverter look after it. Both of the following work well for travel and require little power.

ZI by Human Design Medical
EZEX Travel CPAP by Transcend

The lifespan of a CPAP varies from one unit to another. My healthcare insurance provider says they will replace mine after 5 years though I've only had one fail and it went at 8 years. If your wife's unit is getting old or if you plan to travel a lot, one of these small travel units might be an easy solution.

MnTom · 08-07-2014, 09:17 AM

Quote:

Originally Posted by calguy42

I may look in to the 2 golf cart batteries. I have read on other posts about doing this. When I said dry camping I should have clarified it a little bit. It would only be for one night on the road (such as stopping at a Wal-Mart parking lot) and the next night in a campground.

You will have no problem. I also have two golf cart batteries. I have a C-Pap and was broke down in Michigan for 48 hours and no shore power. My machine is 24volt so I used a 800 watt inverter for two nights plus staying in my trailer. My wife and I didn't use the lights much, but then I wound up spending one more night without shore power and far as I could tell there was plenty of power yet in the batteries. In other words I went three days and nights on the batteries alone.
Tom

BFlinn181 · 08-07-2014, 09:34 AM

For overnight at Walmart occasionally, two 6 v batteries will be more than adequate. If you look to buying a new C-pap in the future, I'd look for one that works on 12 v and 120 v because you definitely lose efficiency in going from 12 v to 120 v with an inverter.

ronspradley · 08-07-2014, 03:28 PM

To test what your current set-up will do, the next time you are camped with shore power, just turn off your converter. That will show you what your unit will do on just battery, with the back-up of shore power if you need it. ☺

ronspradley

.

Dakota98 · 08-10-2014, 06:55 PM

Been using a CPAP for about 18 years or so & when it came to camping I didn't want to use my coach batteries so I purchased a small 35amp deep cycle battery ($50) dedicated to that purpose & run it using the DC adapter. My last trip was for 3-nights of use & when I returned home, I found the battery to still have about 50% power. The battery is very small & easy to handle, measures about 7x7x4 or so. If needed, I do have a generator & battery charger also.