How Does an Oven Heating Unit Work?

Basic Oven Operation

• Whether powered by electric or gas, ovens are heated to temperatures set by dials on the front or top of the range or built-in oven. The dial is set to the desired temperature and stops heating when the appropriate hotness is achieved. As the food cooks, the oven switches off and on to maintain the preset temperature. Some ovens have indicator lights to let cooks know when the oven reaches the preferred temperature.

Electric Oven Units

• Electric oven units are made from coils enclosed in metal casings with a wire running down the center that heats the metal sheathing. The top units in electric ovens help heat it for baking and also serve as broiler elements. For baking, both units are activated, glow red as they reach desired temperatures and turn black when fully preheated. The top unit is activated by itself for broiling and is used to cook or brown food from the top. Most electric ranges are powered by a 240/120-volt unit. The 240 volts power the elements and the 120 volts power the accessories. A thermostat senses and controls the internal temperatures.

Gas Oven Units

• Gas oven units are controlled by small gas valves attached to the range's main gas line that supply fuel to the oven and burners. The gas flow for the oven is activated by a knob that ignites the element. A safety valve in the oven turns off the flow if there is no ignition detected, to prevent the buildup of toxic fumes. When the unit reaches the right temperature, the gas flow halts and the flames dissipate. Broiler units in gas ovens are in drawers under the stovetop or under the oven. Gas ovens can be configured to operate on natural or propane gas.

Troubleshooting

• Units in both gas and electric ovens require occasional replacement, but if they fail to operate, also have the repair technician check the temperature control and oven selector switches to determine if they function properly. Also have the technician check the capillary tube attached to the oven walls to ensure its sensors are correctly assessing the internal temperature of the oven.