Water leaking from Lennox indoor air handler or furnace cabinet during cooling; puddles form around the unit.

Safety: Turn off power to the indoor unit. Water and electricity are a dangerous combination.

• 1. Clear drain line: Use a wet/dry vacuum at the outside drain termination to remove clogs. Flush with water and a small amount of vinegar or condensate cleaner.
• 2. Inspect drain pan: Remove coil access panel and inspect the primary pan for cracks or rust-through. Temporary epoxy repair may help, but pan replacement is the long-term fix.
• 3. Verify slope and trap: Ensure the drain line slopes downward and that a proper trap is installed if required by the Lennox installation manual.
• 4. Clean secondary pan and check float switch: If equipped, clean the auxiliary pan and verify the float switch is working and not stuck.

Note: Persistent leaks can cause mold and structural damage; address promptly.