The answer to 'why is my evaporator coil leaking water' is that the evaporator coil is likely clogged, causing water to back up and leak out. This can happen due to a buildup of dirt, dust, or debris on the coil, which prevents proper drainage. Other common causes include a problem with the condensate drain line or a malfunctioning condensate pump.
If the leak is minor, you may be able to fix it yourself by cleaning the coil and checking the drain line. However, if the leak is significant or you're unsure of the cause, it's best to call a professional HVAC technician to diagnose and repair the issue. They can properly inspect the system, identify the root cause, and make any necessary repairs to stop the leak and prevent further damage.