Patent ID: 6965732

Claim:
A method of heating a liquid, comprising: electrically heating a heating plate, via an electrical power supply, to a predetermined temperature above the boiling point of the liquid to be heated; wetting the heating plate with the liquid to be heated; and controlling said electrical power supply to maintain said heating plate at said predetermined temperature, such that when the heating plate is not wetted by said liquid, the electrical power supplied to the heating plate is automatically maintained at a relatively low value; but as soon as the heating plate is wetted by said liquid, the electrical power supplied to the heating plate is automatically increased to a relatively high value by the load produced by the wetting liquid, and is automatically controlled thereafter in response to said load to maintain said heating plate at said predetermined temperature, unless and until the liquid is completely evaporated, whereupon the electrical power supplied to the heating plate is automatically reduced to, and maintained at, said relatively low value until the heating plate is again wetted by the liquid to be heated.