Ideal thermistor kit 174087

This Ideal thermistor kit contains a lead and O-ring and is designed for compatibility with Evo, Icos, Isar, Mexico, Elise, Esprit, Esprit 2 and Istor boilers. The thermistor decreases circuit resistance in line with temperature increases. A boiler's printed control board (PCB) sends a current to the thermistor, deciding whether a decrease or increase in heat is required by reading the relative resistance.