Upon arrival technician inspected the system and found that the system is a single stage system with three zones. Which is causing an abundance of water to build up in the drain line, with the addition of the algae this causes a lot of issues.The minimum work that needs to be done is to replace the drain pan and drain lines. In order to solve all the issues, the customer will need to replace the system with either two systems or an 18 seer to 20 seer system.