How many watts does a CPAP heated humidifier use?
Updated
Running watts
50 W
Starting watts
50 W
Energy per day
400 Wh
A CPAP heated humidifier typically draws about 50 watts while running. At about 8 h of use a day, that is roughly 400 Wh per day. These are typical values from generator wattage charts: the label on your own appliance (or its EnergyGuide sticker) gives the exact figure.
What size generator do I need for a CPAP heated humidifier?
Plan for at least 60 W: 50 W to get through the start-up surge, plus a 20% margin so the generator never runs flat out. Of the common sizes, a 2,000 W generator is the smallest that fits.
| Generator | Can it run a CPAP heated humidifier? |
|---|---|
| 2,000 W | Yes |
| 3,500 W | Yes |
| 5,000 W | Yes |
| 7,500 W | Yes |
| 10,000 W | Yes |
| 15,000 W | Yes |
How long will a power station run a CPAP heated humidifier?
Running continuously at 50 W, assuming 85% of the battery is usable. The station's AC output must also handle the 50 W start-up surge.
| Battery capacity | Runtime |
|---|---|
| 1,000 Wh | about 17 h |
| 2,000 Wh | about 34 h |
| 3,600 Wh | about 2.6 days |
Running more than one appliance?
Starting surges don't add up the way running watts do. Pick everything you want to power to get your real number.
Open the CPAP Battery Backup CalculatorFrequently asked questions
What size generator do I need to run a CPAP heated humidifier?
At least 60 W: 50 W to cover the start-up surge, plus a 20% safety margin.
Can a 2,000 watt generator run a CPAP heated humidifier?
Yes. 2,000 W covers its 50 W starting surge with room to spare.
Can a 3,500 watt generator run a CPAP heated humidifier?
Yes. 3,500 W covers its 50 W starting surge with room to spare.
How long will a 1,000 Wh power station run a CPAP heated humidifier?
About 17 h, assuming 85% usable capacity, as long as the station's AC output is rated for 50 W of surge.
Never run a generator indoors or in a garage: see the CPSC safety guide.