Humidifier for Camping?

I'm looking for a humidifier to use when I'm camping. I currently use my ResMed unit as a passover (I make sure it's turned off) unit, but it's not enough.
Something propane fired (Iknow, it sounds crazy) would be preferred, but I guess I'll do whatever I need to. I'd also be willing to rig something else; anyone done this?

What kind of camping? You need electric power to run the xpap fan. The incremental power needed for the humidifier isn't incrementally that great. If you are running on battery power or especially a generator, you should have enough power for a whole night before recharging is needed. If you are talking about primitive camping, then any xpap is impractical.

Note this thread viewtopic.php?t=9828 points out that the Resmed S8 and humidifier are not designed to run on 12 volt power.

Sleeprider wrote:The incremental power needed for the humidifier isn't incrementally that great.

Depending on the flow generator and humidifier settings, it can be up to 200% to 300% of the power needed to run the flow generator by itself.

Heating anything, even at the very mild heat levels that humdifiers run at, requires significantly more energy than running the electronics and small motor in a flow generaor.

Cheers,

Bill

Rattleman wrote:I'd also be willing to rig something else

I have no specific suggestion for a solution, however, the engineering problem you need to solve is basically this....

• 1. Mildly heat a volume of water which is adequate to provide your humidification needs for one night.
  
  2. Maintain a fairly constant, but adjustable, low heat in that volume of water over a period of up to 8 hours
  
  3. Have an adequate surface area on the water that enough water molecules are transfered to the air flow over that surface area.
  
  4. Plumb the device into the airflow circuit between the flow generator and mask without materially impacting the overall "impedance" of the air circuit, so that the functioning of the flow sensors in the flow generator is not adversely impacted.
  
  5. Be able to reasonable fill, empty and clean the water container.
  
  6. Determine how to calibrate the heat adjustment, so that you get some degree of predictability between heat settings and the level of humification delivered

There are probably some other factors, such as not agitating the water surface too much, and avoiding heating any plastic materials in the vicinity etc etc, that may also need to be considered.

Cheers,

Bill

If you decide to investigate the use of an inverter (changes 12 volts DC to 120 volts AC) with your ResMed humidifier, you must use a pure sine wave inverter, which is different from the commonly available inverters. A pure sine wave inverter is also considerably more expensive than the commonly available inverters. The type of control circuit that is used in ResMed humidifiers can be damaged if it is used with regular inverters.

There are some older ResMed humidifiers that are not supposed to be used with any sort of inverter.

A humidifier is very difficult to use if you don't have commercial AC power available. A humidifier requires quite a bit of power to heat the water and will discharge a battery very quickly. Almost all humidifiers require 120 -240 AC power, and an inverter causes an additional power drain on the battery. Respironics makes a 12 volt DC powered humidifier which can be powered from a battery, but it still uses quite a bit of power.

A generator has several problems; they are heavy, noisy, and require frequent fuel filling.

The use of other fuels to power a humidifier is going to be difficult. I have never heard of anybody building a CPAP humidifier that uses alternate fuels. Most anything that uses bottled gas, alcohol, or petroleum product would either use a flame or catalytic burner. I would be very leery of using a flame anywhere near bedding, which is where a CPAP humidifier is used. Coleman used to make catalytic tent heaters, which I believe burned Coleman fuel or white gas, which would be safer than using a flame. Another possible danger would be carbon monoxide if you are using it is some sort of shelter.

One answer would be a REAL Passover unit, not as much moisture but no power usage, and probable good enough. I use my XPAP at home with 60% humidity in the air with no water in the HH and turned off. I'm sure outside conditions would be would be higher than in my house. Jim

I have a ResMed VPAP Auto (that I use only for CPAP pressure) with a 3i humidifier. I bought a West Marine SeaVolt AGM 79 deep cycle battery with an AIMS pure sine wave inverter. I also purchased a multistage deep cycle battery charger and a "battery keeper" to keep the battery charged while not in use.

I have found this set up works well for me when I'm out tent camping. I keep the humidifier cranked down to a the lower settings and I find it is not that uncomfortable especially sleeping in cool air and if there happens to be thunderstorms overhead. The outside humidity also helps. If you want to crank up the humidifier, get a longer amh battery (which also means a heavier battery). The battery I have is for 79 amphr for 24 hrs. The electrical math calculations can be confusing but this set up works for me. I have a pressure of 15 so I put a fair amount of load on the battery.

When I sleep outdoors for some reason, I sleep long (8-9hrs) and deep sleep. It's great. I've camped at around 9,000 ft in elevation with no problems. Most of my camping has been in the summer where the temps have dropped to the low 40's to high 30's at night. I once camped without humidification when it was 19 degrees out. I just curled up in my oversized sleeping bag and it was fine.

I'm a fly fisherman so I charge the battery when driving around during the day looking for new fishing spots running the battery charger from a power outlet through the inverter in my truck. You just can't have a charger more than 10 amps (8amp charger is best) or you'll blow a fuse in the truck.

Lastly, make sure your battery/inverter is grounded. I drilled a hole through an aluminum tent stake and run a small gauge solid cooper wire out of the tent to the stake pounded in the ground.

Hope this helps.

What kind of camping? You need electric power to run the xpap fan.

Almost exclusively car camping, i.e. in my slide in truck camper.
I'm currently using ResMed'a power supply with a 12v deep cycle battery. I'd prefer to avoid using a pure sine wave converter and rig up some sort of flame powered unit or something that would be warmed by the camper's furnace. The battery I have right now works great for the cpap, but I doubt it'll have enough stuff to power the cpap AND the humidifier at the same time.
I'm aware of the pitfalls of running the humidifier with non-sine wave power.

If you are sleeping in a confined space, it seems if you boiled up a couple pots of water before bedtime, that might add enough ambient humidity inside your camper to help unaided by an air flow humidifier. Also, if you are sleeping with a fairly warm furnace (that comes on frequently) perhaps a metal pot of water on or near the furnace vent might also help keep humidity levels up.

I have had "rain out" in my mask where I have been slept in damp conditions outside so ambient humidity can be a side benefit to not having an actual humidifier.

I have to mention that keeping a flame burning (even very low) in a confided space while sleeping strikes me as dangerous. With that said, there are some "space heaters" that attach to a propane tank (like for a gas BBQ grill). You can find them at Cabela's and stores of that nature (also on the net). They are very warm and are good for heat outdoors when say eating dinner when it is chilly outside. Flames and lead batteries in close proximity also make a hazardous combination.

Good luck...