Assume a bank of heating strips is rated at 20 K W and is connected to 240 volts. The heat strips operate for 4 hours at a time and are located in an area with an ambient temperature of 96 degrees F. The termination temperature rating of the heat disconnect lugs is unknown. Three (3) Copper conductors installed in a conduit with type THWN-2 insulation are to be used to connect the heaters. What size conductors should be used?

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Electrical Heating Unit

The conversion of electrical energy to heat energy is known as electric heating. The heating system that converts the electrical energy to heat energy for various application is called electrical heating unit. Electricity is employed as the firing mechanism in electric heating systems, which transforms electric current to heat. Electric heaters have heating elements in the form of electric resistors.