A3 is the Daikin code that comes with a deadline, because it is about water. Here is what it means and the right order of moves.
What A3 means
Daikin error code A3 signals a drainage system abnormality. The condensate water your aircon constantly produces is not draining away properly, and the unit has flagged it before the tray overflows. Daikin rates this medium severity, but in a Singapore flat the real risk is water damage, not the aircon. Full table in our Daikin error codes guide.
What usually causes A3 here
Almost always a blocked drain line. Our humidity grows biofilm inside the pipe fast, the slimy stuff customers call aircon jelly, and it narrows the line until water backs up. Next most common: a failing drain pump on units that have one, a dirty drain pan, or a pipe laid with a poor gradient by a previous installer, which was always going to clog early.
What you can safely try
Switch the unit off. Not because the aircon will break, but because every hour it runs makes more water with nowhere to go. If the drain outlet outside is visibly blocked at the mouth you can clear that, but the real blockage usually sits deeper in the line where home tools cannot reach.
What our technician does
Flush the drain line through, clean the pan and float switch, test the pump where fitted, and check the pipe gradient so the fix lasts. If it has been overflowing quietly for a while, we also look for the water damage you cannot see yet.
What it costs
Drainage clearing is one of the cheaper jobs on the list, usually servicing rates unless a pump needs replacing. The expensive version is the one where A3 was ignored for weeks. Rates are published on our aircon repair in Singapore page.
A3 showing right now?
WhatsApp +65 8818 5781 with your model number and a photo of the display. We will tell you honestly whether it is a quick fix, a repair worth doing, or nothing to worry about. Our aircon repair in Singapore service covers every brand with published rates and a 30 day labour warranty.








