The CPAP water chamber is the removable reservoir on your humidifier that holds distilled water. As CPAP air passes over the heated water, it picks up moisture, which prevents the dry mouth, throat irritation, and nasal congestion that dry pressurized air causes.

Replace the water chamber every 6 months under standard insurance coverage (Medicare and most plans). Earlier replacement is recommended if you see cloudiness, mineral buildup, or cracks. Daily cleaning with mild soap extends its life and prevents bacterial growth.

No — always use distilled water. Tap water contains minerals (calcium, magnesium) that deposit on the chamber and heating plate as scale, shortening their life and potentially being aerosolized into the air you breathe. Distilled water is sold inexpensively at any grocery or pharmacy.

Empty any remaining water each morning. Wash the chamber in warm soapy water (mild dish soap) or a 1:1 vinegar-water solution once a week. Rinse thoroughly with distilled water and air-dry completely before refilling. Never put the chamber in a dishwasher unless the manufacturer specifically approves it.