18/04/2026
Seeing red/ pinkish liquid flowing out from air-con drainage pipe?
Sometime customers are very worried when they see red/ pinkish liquid flowing out from their aircon drainage pipe in the toilet. They will ask us if it is toxic, harmful, or if it is refrigerant leakage.
Not to worry too much. Red liquid or slime from aircon condensate water is typically a bacteria-driven biofilm (Serratia marcescens), not refrigerant.
This is common in humid environments where airborne bacteria, dust, and rust mix with moisture, turning the discharge red, pink, or orange.
When you see it next time, do not be alarmed.
Yours Truly,
Dr. Cool
YOUR AIRCON DOCTOR