Abstract: An electric cartridge heater for use as an immersion heater in a steam table tank has a tubular elongate stainless steel sheath with a curved inner surface attached to a riser tube adapted to be connected to a wall of the tank and contains an electric heater element. A copper heat transfer member having an enlarged, curved surface complementary to the inner surface of the sheath is urged into close, intimate thermal contact therewith and transfers heat from the sheath to a bimetal thermostat for turning off the heater element in response to a rise in temperature of the sheath above a predetermined level.

Abstract: A apparatus for maintaining precooked food at a desired temperature includes a stationary hollow housing mounted in the bottom part of a warmer for holding a quantity of food. The housing defines a cylindrical passage having an entrance through a wall of the warmer. A removable cylindrical member containing an electric resistance heater is inserted into the passage and is freely rotatable therein. A locking mechanism including a lug secured to a hub at the entrance of the housing and insertable into a circular guideway of a rotor attached to the outer end of the sleeve through a slot in the rotor secures the sleeve within the passage.