The part(s) or condition(s) listed below for the symptom Oven won't turn on are ordered from most likely to least likely to occur. Check or test each item, starting with the items at the top of the page.
The igniter is the most commonly defective part for a gas oven that won't turn on. The igniter has two main functions. First, the igniter draws electrical current through the oven safety valve to open it. Second, the igniter gets hot enough to glow and ignite the gas in the burner assembly. If the igniter gets weak, it will fail to open the safety valve correctly. If the valve does not open, the oven will not heat. To determine if the igniter is defective, observe the igniter when the oven is on. If the igniter glows for more than 90 seconds without igniting the gas flame, this indicates that the igniter is too weak to open the valve. If the igniter is weak, replace it. If the igniter does not glow at all, use a multimeter to test the igniter for continuity. If the igniter does not have continuity, replace it.
Electric ovens require 240 volts of alternating current. Gas ovens require 120 volts. If an oven won't turn on there could be an incoming power problem. To determine if the electrical outlet is providing sufficient voltage, use a multimeter to test the incoming power at the wall socket.
One of the wires that supply power to the oven element or igniter might be burnt out. These wires commonly burn out near the heat source. To determine if a wire has burned out, inspect the wires leading to the element or igniter. If a wire is burned out, it will often be visibly burnt.
The gas oven safety valve works with the oven igniter to provide gas to the burner. If the safety valve fails, the oven won’t heat. However, this is rarely the cause. Before replacing the safety valve, first test all of the more commonly defective oven components, particularly the igniter. If all of the other heating components are working properly, use a multimeter to test the safety valve for continuity. If the safety valve does not have continuity, replace it.
The temperature control thermostat monitors the temperature inside the oven and cycles on the heat when the oven temperature gets too low. If the temperature control thermostat fails, the oven won’t turn on. However, this is not very common. Before replacing the oven thermostat, first check more commonly defective components—specifically the igniter and the bake and broil elements. If these components are not defective, the temperature control thermostat might be at fault. The temperature control thermostat cannot easily be tested. If you suspect the thermostat is defective, replace it.