Humidifier wattage - Anyone know Pse?

[Kingsway]

I'm just wondering if anyone knows the wattage of a typical CPAP humidifier element?

I see  (from pix elesewhere) that the Resmed A10 element is rated at 8.5 ohms - but don't know what voltage is used..

For one reason or another, I am currently using a DIY humidifier,  but without heating. Air simply blows across the water.
 But it should be simple matter to rig up a silicon heat pad of a suitable rating.

I'm guessing  a 10 to 20 watts heater might be sufficient????


BTW  Here in the UK, the relative humidity is rarely below 60%, and my Sefam S.Box was givin to me without a humdifier.  I've managed for several months, but have increasing problems with my nose drying out, and becoming very itchy!!   I've requested a humidifier from the NHS and they have agreed to let me have one, but told me they are on back order.  (That was two months ago!)

[Sleeprider]

If it helps, Resmed voltage is 24 Watts DC. Temperature range is lower than you might think with a range of only 85 to 95 degrees F or 30-35 C.

[Kingsway]

So if the element is running at 24volts,  we could be talking about 67 watts - 2.8 amps which seems an awful lot for the flimsy ribbon cable that's used in the Resmed A10.

At 12 volts, however, it would be just  16 watts  or  1.4 amps

Hmnnn...

Ive decided to buy a set of 4  x 15w 12v silicon pads.   (2in x 4in  - 50mm x 100mm)    I can  start with one pad - then add others in parellel if necessary, giving me from 15  to 60watts.


  They're cheap enough on Amazon...

https://www.amazon.co.uk/gp/product/B0BG...0VMY&psc=1

[robbob2112]

I had a conversation with the chatgpt AI and it came up with 21.1 watts for a heater to do it in 20 minutes.

But, if you google for the part number , r370-791, it comes up and you can just install the real thing.  You need the plate, a tank, and the thermal fuse to make it work.  Total cost is about $60usd

Robert

[Kingsway]

Aha!  I didn't think to try chatGPT!   

When I did so, a couple of minutes ago, it came up with 20 to 60 watts!  

So, my purchase of four 15watt sillicin pads should do the job.  I can even switch in extra pads to go between 15, 30, 45 and 60 watts!

This is just a temporary setup until my local clinic give me a (free/) humidifier for my Sefam S.Box. (God bless the NHS!)

[robbob2112]

I think there are a few cconsiderations.  When I used it I told it 500ml water, raise to 90f, and 20 minutes.  Since heaters are either on or off that means the machine is doing PWM or some other method to do a duty cycle wave with feedback from a thermistor to monitor temperature and keep from overshooting to much.

The pwm accounts for how the wires can be so small, it isnt carrying 3 amps continuously.  3d printers use tha same sort of feedback loop as to reptile heaters.

[Kingsway]

I can't believe the prices  of stand-alone  universal humidifiers!    'Only' $299" reduced from $499!!   Gold-plated maybe...

 https://repap.com/product/fp-sleepstyle-...furbished/

Many items/parts  cost double the US price here in the UK. n Even if available at all -  Sadly, shipping costs from ther US are exorbitant.  I recently saw a hose muffler for about $8.00, but shipping was around $50 !

Sadly there seems to be no Chinese equivalent (shipping usually free or minimal cost)

[UnicornRider]

I believe that includes the SleepStyle CPAP machine.  Not just a stand alone humidifier.

[Kingsway]

I believe that includes the SleepStyle CPAP machine.  Not just a stand alone humidifier.

Oh, you're right - that  does make a lot  more sense!

[robbob2112]

Seems like the simplest diy humidifier would be a small sealed tank, aquarium heater, and then feed the air to pass over the water. A plain pap hose could be cut in half to do the connection. Maybe put one end under the water with a small vacuum break hole just above water level to prevent siphon when it is turned off.