06-22-2015, 12:55 PM
(This post was last modified: 06-22-2015, 12:58 PM by GWild.)
Folk need to remember that warm air flowing over a cool surface will cause moisture in the air to condense out of that air. This means the air will be dryer as well as perhaps a bit cooler. The other side of it is that it takes quite a lot or energy to cool volumes of air we breathe. Not to mention the risk of water puddling in the hose.
Consider making the xPAP unit part of an evaporative cooler. Find a shallow tupperware-like cake pan, find a piece of Celdek to set in it, find a wire shelf to set on top the celdek, place the xPAP on the wire mesh, cover the xPAP with a cake cover, plastic sheet or towel so air is pulled through the Celdek, add water, and go for it.
Not sure where the max humidity specs are for your xPAP, but this will get you cooler air ... Another way is to buy a small $89 fridge, drill a 1" hole for the hose to fit and plumb your hose through it; then place the xPAP inside the fridge. Most xPAPs will run at 40 F. But be careful when pulling the data card for reading; be sure to let it warm up before placing it into a reader outside the fridge (condensation - so same goes for taking the xPAP out of the fridge).
As a note: I am mostly joking when making these suggestions. Both silly ideas have negative consequences. A simple anti-clockwise twist of the thermostat dial in your house will give you much better results.
06-22-2015, 01:27 PM
(This post was last modified: 06-22-2015, 01:47 PM by surferdude2.)
If I took on your project, I would use a small refrigerator to cool the air. Do NOT get one that doesn't have a mechanical compressor since it will not have enough capacity for your purpose. Do NOT place the hose in the refrigerator but instead place a flex duct in the refrigerator up near the freezer section and run it over to the air intake on the cpap (seal it as best you can so very little room air can get in). That will allow the cpap machine to draw its intake air from inside the refrigerator. You must also leave the door of the frig slightly ajar in order for the necessary make-up air to enter.
This will allow you to have cooler air to breathe and not have any rain out problem. The cooled air will not condense inside the hose since that would defy the laws of physics. If you get any condensation at all, it will occur on the outside of the hose since that's where warm moisture laden air will contact a cooler medium. I dare say that won't happen since you won't get air down to that low temperature.
Not knowing the btu cooling capacity of the refrigerator you will be testing, the room ambient air properties and your air flow volume, I can't guarantee how much cooler the air will be or even if the refrigerator you buy will tolerate being run with that sort of loss. I suggest you get the larger model for starters, if it doesn't work, your research can end. Hopefully excess noise won't be a problem. The back pressure on the compressor will be higher than normal and that may overheat the unit and cause it to cycle on the thermal overload. I doubt the Delta T will be any more than 3° F. so if you need more than that, read on.
You could test this setup without having to damage the refrigerator beyond the point of not being able to return it if it doesn't work as well as you like. Most big retailers will allow you a free trial, usually 30 days.
If it turns out you need more capacity than those small refers can supply, consider getting & installing a small 115 volt room A/C. Ducting the output from it while running it with a slow fan speed will give you considerably cooler air then room ambient. You can expect a Delta T of approximately 10° F. for most small room A/C's.
Sounds like the begging of a Rube Goldberg contest.
Using FlashAir W-03 SD card in machine. Access through wifi with FlashPAP or Sleep Master utilities.
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