Thermally sensitive controls

摘要

A thermally sensitive control 2 is provided in or for use in a liquid heating vessel having a sheathed electric heater 92 mounted to a diffuser plate 80 provided on its base 8. The control comprises first 10 and second 12 actuators arranged to make good thermal contact with the vessel base. Biasing means 20 are arranged to exert a variable biasing force on the second actuator 12 so as to vary its operating temperature in use. The actuator 12 engages a region 84 of the diffuser plate 80 which is surrounded by 3 spaced slots 86, 88, and 90 which act to isolate the region 84 from the heater 92 so that its temperature reflects more accurately the temperature of the base of the vessel and that of the liquid being heated inside the vessel.