How the System Works
The oven control, oven ignitor and oven gas valve are connected one after the other. When you turn on the oven control, it passes electric current to the ignitor, which contains a resistance heating element. The electricity heats the element to bright yellow heat. Once the ignitor reaches the correct operating temperature, it allows electric current to pass to the gas valve. The electric current from the ignitor signals the gas valve to open and send fuel to the oven burner so the hot ignitor can ignite the gas. Power must continually flow from the oven control through the ignitor to the gas valve for the oven burner to operate.
When the oven reaches a preset maximum temperature, the oven control cuts the power to the ignitor and gas valve, cutting off the burner flame. When the oven temperature drops to a minimum value, the oven control once again sends power through the ignitor to the gas valve. The oven control continues cycling between minimum and maximum points to maintain the temperature the control is set for. A normally functioning ignitor typically takes 60 to 90 seconds to reach operating temperature and open the oven gas valve.
Gas oven glow-bar ignitors can get weak with age and cause oven operating problems. Even though an oven ignitor is glowing, it may not be at the correct operating temperature to allow current to pass onto the gas valve. A weak ignitor may get hot enough to allow the oven to work for one heat cycle, but never cycle back on. If a break occurs in the electric circuit that ties the controller, ignitor and gas valve together, neither the ignitor nor oven burner will work.
If the whole oven ignition/valve circuit is dead, you need to use a continuity tester to check each connection and component for a complete electrical path, starting with the oven controller, then the ignitor and the gas valve. Any component without continuity is bad and must be replaced. If the ignitor glows but the burner doesn’t come on, you need to check the amperage being drawn by the ignitor. Ignitors with a rectangular white or beige base should draw between 3.2 and 3.6 amps, while those with a round base or a blue rectangular base should draw between 2.5 and 3 amps. If the ignitor doesn’t draw enough power, it is bad and must be replaced. If the ignitor tests OK, check the gas valve for continuity.