Airflow4 min
Condensate overflow
A wet switch is a symptom. Find why the water is not leaving.
Path
- Primary drain pitched, trapped where the OEM requires a trap, vented if the trap will siphon.
- Secondary / pan switch should break Y or R per local practice — know what you are jumping before you jump it.
- Pumps: check the reservoir, float, check valve, and lift height vs rating.
Why it backs up
- Algae in the trap, a sagged vinyl line, a crushed riser, or a dry trap pulling air.
- A plugged primary with a disconnected secondary is how you stain a ceiling.