Clogged drain pan
There isn’t an air conditioner model that doesn’t have a condenser coil. This produces water from the difference of temperature. This water usually drains in some special pans.
Checking the drain pan
To have access to the drain pan you need to open the cooling coil cabinet. See if the pan is flooded. If it is, then it’s a sign that the system is clogged.
Cleaning the drain pipes
Bleach and water usually solve the problem with clogged pipes. If this isn’t a solution, then use a pump to remove any objects blocked in the drain pipes.
Leaks can be easily spotted before they become a real problem. Just look for water stains around the AC unit. If there are any, than start doing a check-up of the unit.