Daikin · Air Conditioner error code

A3Drain water level too high

Cross-checked Power off, standard tools

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Related diagnostic guides

Guide · Air Conditioner

Portable AC shows water-full code or keeps filling

In humid weather or dry mode, a portable can collect water faster than it evaporates it. Drain and set up a continuous drain first; a code with an empty tank points to the float switch or internal pump.

4 steps ~30 mineasy

Guide · Air Conditioner

Central AC shut off by the condensate float switch

Float switches cut the cooling circuit when condensate backs up, usually from an algae or dust clog in the drain line or a failed condensate pump. Clear the drain, let the switch dry/reset, and find out why it backed up. Never bypass the switch.

5 steps ~45 mineasy

Guide · Air Conditioner

Mini-split indoor unit dripping water

Indoor head leaks are almost always drain related: clogged pan or line, poor line slope, a failed condensate pump, or the head not level. Ice on the coil from low airflow or low charge is the next suspect.

6 steps ~45 mineasy