Display shows “ADD WATER” and brewing will not start even though the water reservoir appears to have water.

Safety first: Unplug the coffee maker and allow it to cool completely before handling the reservoir or internal parts.

• Check water level: Remove the water reservoir, fill it to the MAX line with fresh water, and reinstall it firmly. Make sure it is fully seated and not tilted.
• Reseat the reservoir: Inspect the bottom of the reservoir and the mating area on the base for debris, coffee grounds, or scale. Wipe both surfaces with a damp cloth and dry thoroughly, then reinstall the tank with a firm downward push.
• Reset the unit: With the tank properly seated and filled, plug the brewer back in and press the power/brew button. Some OXO models clear the message after a power cycle.
• Descale the machine: If the message persists and the tank is full, run a full descale cycle using a manufacturer‑approved descaling solution. Mineral buildup can interfere with internal water level sensing.
• Inspect sensor area: On models with a removable base plate under the reservoir, check for corrosion or moisture around the water level sensor contacts. If corrosion is present, gently clean with a cotton swab lightly dampened with white vinegar, then dry completely before use.
• When to stop: If the machine still shows “ADD WATER” with a full, correctly seated tank after descaling and cleaning, the internal level sensor or reservoir sensor interface may be faulty. Do not attempt to open the housing unless you are qualified; contact OXO support or a professional technician.