Cooling condensate drain overflow

A blocked, disconnected or poorly sloped drain allows cooling condensate to wet nearby finishes.

Failure path

• Step 1: Cooling coil removes moisture from air.
• Step 2: Condensate collects in a pan.
• Step 3: Drainage is restricted or disconnected.
• Step 4: Water overflows or backs up.
• Step 5: Staining follows equipment runtime rather than rain.

What makes this pathway plausible

The timing, location and operating or weather trigger should repeat. A diagram shows a mechanism; evidence from the actual house determines whether it applies.

Best next observation

Record the trigger and compare the nearest materials, components and routes before opening finishes or choosing a repair.

Verification after repair

Recreate the original trigger when safe, then confirm the symptom does not return and affected materials are stable or drying.