Patent ID: 7394042

Claim:
A banquet cart comprising: a body defining an interior compartment, wherein said interior compartment is accessible by at least one door; and a heater unit including at least one heat retaining element made of a plastic solid to solid phase change material, an element heater that heats said at least one heat retaining element, and a central heater to heat said interior compartment, wherein said at least one heat retaining element warms said interior compartment, wherein said central heater is active to heat said interior compartment and said element heater is inactive during a first mode of heating, wherein said central heater is inactive and said element heater is active to heat said at least one heat retaining element during a second mode of heating which is after said first mode of heating, and wherein said central heater and said element heater are inactive and said at least one heat retaining element warm said interior compartment during a third mode of heating which is after said first mode of heating and said second mode of heating.