The thermistor decreases the current resistance as it gets hotter. The printed circuit board sends a current to the thermistor and can tell whether a decrease or increase in heat is needed by the relative resistance in the thermistor.
Fits a Number of Appliances
Technical specification
Toilet Cistern CapacityFTW--ERP RatingNot ApplicableSupplier Part Number1.883.44.3.0Brand NameMira