Whether you have an electric or a gas oven, at some point, usually due to wear-and-tear, the oven may stop heating. This guide lists the most common components that can cause the heating issue. Read on to diagnose and fix the issue.
Before repairing the oven, make sure to disconnect the power or gas.
If you have an electric oven, the most common cause of the oven not heating is a burned-out or broken bake or broil element. If an element or its wiring is not responsible, the oven may not heat because of a blown thermal fuse or defective thermostat or sensor. If these parts are defective, they will need to be replaced. If none of these parts are responsible, the oven’s main control board may need to be replaced.
1. Bake/Broil Element
Over time, either the bake or broil element may become defective and need to be replaced. The elements can be inspected visually for damage and tested with a multimeter to determine if they need to be replaced.
To check the elements:
- Inspect the elements for breaks or blistering. If there is a break, it will need to be replaced. If there is blistering, test it with a multimeter to determine if it needs to be replaced.
- Remove the element and test it with a multimeter for continuity (a continuous electrical path). If there is no continuity, it will need to be replaced.
2. Power Supply
Check your electrical panel to see if a breaker has been tripped or a fuse has been blown. The power outlet can also be checked with a multimeter to confirm the outlet is providing enough volts to heat the oven.
To test the power outlet:
- Set the multimeter to “Volts AC.”
- The multimeter should return a reading that is between 210 and 240 volts.
3. Element Wiring
The bake or broil element’s power supply wires can sometimes become loose or burn out. The wiring will need to be visually inspected for signs of loose or corroded wires.
To check the wires:
- Check inside the oven, where the bake and broil elements are attached to the rear of the oven, for signs of damaged wiring.
- Disconnect the power and remove the back panel of the oven. Inspect the wiring of each element for signs of damage.
- If a wire is damaged, the entire element will likely need to be replaced.
4. Thermal Fuse
Some ovens feature thermal fuses, which are tripped when the oven gets too hot. A blown thermal fuse will shut off power to the oven. If your oven has a thermal fuse, it can be checked with a multimeter to determine if it needs to be replaced.
To check the thermal fuse:
- Remove the thermal fuse from the oven.
- Check the thermal fuse for continuity with a multimeter.
- Replace the thermal fuse if there is no continuity.
5. Check the Thermostat or Sensor
Depending on your model, the oven may be switch-based, with a thermostat and sensing bulb, or feature an electronic control board that uses an oven sensor to monitor the oven’s temperature. If the thermostat or sensor is defective, the oven may not heat. A multimeter can be used to measure the sensor’s resistance at room temperature.
To check the sensor:
- Remove the sensor from the oven.
- Place the multimeter probes inside each of the pins on the temperature sensor’s electrical plug.
- Set the multimeter to “Ohms,” or the “2K” or “4K” setting on a manual ranging multimeter.
- If the multimeter reading does not show close to 1100 ohms of resistance, the sensor will need to be replaced.
The most common cause of a gas oven not heating is that the igniter or spark electrode is defective. A defective thermostat is the second most likely cause of the heating issue. The wiring should also be examined for signs of burning or a shorted circuit. If none of these components are defective, the safety valve and control or relay board should be checked for damage.
1. Igniter or Spark Electrode
Depending on the type of gas oven, it will either feature an igniter or spark electrode to ignite the gas and heat the oven. If there is a fault with the igniter or the spark electrode, the oven will not heat.
To check the igniter:
- Open the oven and remove any shields or covers.
- Observe the igniter to see if it is glowing when it has been activated.
- If the igniter is glowing but not igniting the gas after 90 seconds, the igniter is likely defective and will need to be replaced. If the igniter is not glowing, you should remove the igniter from the oven and test it with a multimeter. If the igniter does not have continuity, it will need to be replaced. If the igniter has continuity, the issue may be caused by the thermostat.
To check the spark electrode:
- Remove the spark electrode from the oven. With most ovens, it can be disconnected by unplugging the wire connected to it inside the oven.
- Examine the spark electrode and tube for cracks or damage.
- Replace a damaged spark electrode.
Depending on the type of gas oven, it may use a thermostat to monitor the temperature in the oven. The thermostat shuts off the voltage to the igniter when the desired temperature is reached. If the thermostat is defective, the igniter may not be receiving any voltage, which stops it from igniting the gas and heating the oven.
- Remove the thermostat from the oven.
- Test the thermostat with a multimeter for continuity. If there is no continuity, the thermostat is defective and will need to be replaced.
3. Loose or Burnt Wire Connection
The igniter or electrode power supply wire will sometimes burn out close to the heat source. If the wire has burned or become loose, the igniter or spark electrode will likely be unable to ignite the gas to heat the oven. Depending on the type of gas oven, you may be able to disconnect and replace the wire, or the part itself may need to be replaced.
4. Defective Safety Valve
If none of the above parts have failed, the oven may have a defective safety valve. When working correctly, the safety valve opens to release gas into the oven burner tube. If the safety valve is defective, gas will not be released, and the oven will not heat.
To check the safety valve:
- Remove the safety valve from the oven.
- Check the safety valve for continuity with a multimeter. If there is no continuity, replace the safety valve.
5. Malfunctioning Oven Control Board
Some gas ovens feature an oven control or relay board to control the electrical current being sent to the bake and broil circuits. If none of the above components are defective, a faulty oven control or relay board may be responsible for the oven not heating. If you suspect the oven control or relay board is defective, inspect the board for signs of burning or a shorted-out component. If the board is defective, it will need to be replaced.