Most modern ovens use an electronic control board
to control the oven functions. These models will use the control board to operate the oven safety valve on a gas range or oven, and the bake and broil elements on an electric range or oven. If there is no power to the igniter circuit, or the element circuits, then you should check the control board to verify that there is power at the appropriate output relay. These are live voltage checks and should be performed by qualified persons only. If there is no output voltage then the control should be replaced.
The oven burner igniter
commonly known as the hot surface igniter is used in modern gas oven burners to open the gas valve and to ignite the gas. As the igniter draws electric current it will heat to a high temperature and glow, as well as cause the bi-metal in the oven safety valve to warp and open the valve releasing the gas to be ignited. This sequence normally takes about a minute. Igniters come in both flat and round styles and are very fragile. If the burner does not light then you should check the igniter first. If the igniter does not glow at all, then check for power to the circuit. This is a live voltage check and should be performed by a qualified person. If power is present then the igniter may be open circuit and can be checked for continuity with a multi-meter. If the igniter is glowing, but the burner is not lighting, the igniter may be weak and still be at fault because it requires a certain amount of current draw to open the valve.
This check requires the use of an amp meter and should be performed by a qualified person. If the igniter is defective then it must be replaced.
The oven sensor
: works with the oven control board to regulate the oven temperature. If there is an oven temperature problem, this sensor might be defective. The sensor can be tested by using an ohm meter. As temperature rises, the resistance measurement also rises. The manufacturer of the oven sensor determines the correct resistance, Oven temperature problems can be caused by other things, but this is one of the common causes.
Beware on some models now most of these ovens they are electronic and they are integrated into the control itself
some different sensor ohm readings at room temp. approx 16 ohms at room temperature and at 350?F it is 29~33 ohms.
The oven safety valve
(also called the gas valve) is the part that ensures that gas is not released until the igniter has reached the correct temperature needed to ignite the gas. While this part can fail, it is uncommon. If the hot surface igniter does not glow you should first verify that you have voltage to the circuit. This is a live voltage check and should be performed by a qualified person. If voltage is lost at the valve terminals then you should verify the continuity of the bi-metal in the valve using a multi-meter.
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