CONTROLS FOR WATER HEATING APPLIANCES

摘要

An electrically heated water boiling appliance is arranged to be capable of selectively providing boiling water and water at a predetermined lower temperature (suitable for example for making coffee). The appliance has a first thermally-responsive switch which is arranged to be exposed to steam generated when water boils in the appliance so as to cut off the supply of electrical energy to the heating element of the appliance, a second thermally-responsive switch connected in series with the first switch and arranged to cut off the supply to the heating element at a predetermined lower temperature, and a manually-operable selector switch for taking the second switch out of circuit when it is required to boil water in the appliance. The first, steam sensitive switch and the selector switch can conveniently be formed as a unitary switch structure in which a bimetal moves a trip lever to determine the condition of a first pair of switch contacts, and a third switch contact is provided which co-operates with one of the first pair of switch contacts to define the selector switch, a manually operable lever being movable interactively with the trip lever to determine the state of the selector switch. The appliance also has an element protection control for cutting off the supply to the heating element in a sensed element overtemperature condition.