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Level sensor
Generic term for any device that measures water level — covers conductive autofill probes, capacitive sensors, optical sensors and float-based switches.
Category: Water System
An electronic sensor — usually a conductivity probe — that detects the water level inside a tank or boiler. Triggers the pump to refill when level drops below a set point.
Why it matters — Level sensors prevent the steam boiler from running dry (which damages the heating element) and protect the pump from running without water (which damages the pump itself).
Good to know
- Scale on the probe is the most common cause of failure. The probe relies on water's electrical conductivity to detect level; scale insulates it.
- Most probes can be removed, descaled, and reinstalled. If conductivity testing still fails, replacement is cheap and quick.