CPAP precooler

I am looking to make a precooler for air entering my CPAP so that after the machine increases the pressure it isn’t so warm on my face. I know that CPAP machines only increase the pressure enough to make the temp rise a degree or two, but it seems like more on the face. My pressure rate is 8.9 cmH2O at a volume of 17 l/min. What capacity of peltier chip would I need to get a 5-15 degree F temp drop?




If I’ve figured correctly, assuming dry air and no condensation you’d need about 2W of thermal power to achieve a 10°c temp change. So probably at least a 10W rated peltier.

It’s unlikely that the unpleasant sensation you describe is a result of heating due to compression. Many CPAP devices incorporate a heating element for humidity control, and if a mask-type interface is being used, that in itself can produce unpleasant sensations of warmth due to exhaled moisture and air being held close to the face.

Thank you. I have the heating all turned off, so it isn’t that. I could see the warmth of exhaled air as being problematic. Should one have some sort of thermostat system to control cooling?