Gas Stove Top
Each surface burner knob on the stove top controls a burner valve. When the knob is turned to the right position, the valve opens allowing gas to flow from the manifold. As the gas travels through the burner tube, it is directed into the venturi where it combines with air to create the proper mixture needed for combustion. At the same time, the spark switch closes allowing 120 volts of alternating current to travel to the spark module that produces high-voltage pulses to all of the electrodes. The pulses creates spark between the electrode and the grounded burner cap. This spark ignites the gas and air mixture at the burner head thereby producing a blue flame with an occasional yellow tip. One of the most common problems you may come across with this type of electronic ignition system are the electrodes sparking continuously, sparking intermittently or not sparking at all. If the electrodes spark continuously, one or more of the switches has most likely shorted closed. This is normally caused by liquid getting into the switch. If this should ever happen, you should unplug the appliance and wait a while until the switches have dried out. If, after plugging your appliance, back in, the electrodes still spark continuously, one or more of the switches has most likely failed and you will need to replace it.
If the electrodes spark intermittently, there is a high chance that the module is faulty and will have to be replaced. If one or more of the electrodes fails to spark at all, this could be due to a faulty switch that prevents the voltage from reaching the module. The module could also be faulty and fail to generate the high-voltage pulses to one or more of the electrodes. Finally, the electrodes themselves may be damaged. To help ascertain this, you can check the electrodes for any cracks.
A gas oven ignition system comprises three basic components: the oven control, the igniter and the oven safety-valve. The oven control could either be switch-based with a thermostat and sensing valve assembly, or an electronic control board that works with an oven sensor. Once you select the bake or broil function, the control sends 120 volts of alternating current to the appropriate igniter. The igniter is wired to the safety valve, and as the igniter starts to get hot, it draws an increased current or amps through the valve. Inside the valve there is a fine metal arm that reacts to the heat generated by the amps. Once sufficient amps have passed through the valve, the arm flexes and opens releasing gas into the oven burner tube. The gas then travels through the burner tube until it reaches the bake or broil igniter. By this time, the igniter temperature is over 2000 degrees farenheit so the gas is easily ignited and the appropriate burner will begin to heat. faber cooktop 4 burner The igniter remains on to keep the safety valve open until the oven reaches the specified cooking temperature. The temperature is monitored by the sensing valve on the thermostat or by the oven sensor. Once the selected temperature is reached, the oven control shuts off the voltage to the igniter. The arm inside the safety valve closes, thereby shutting off the gas supply to the burner. This cycle repeats throughout the cooking process to maintain the right temperature.
You should bear in mind that the cooking temperature specified by the control is only an average. The actual temperature will vacillate throughout the cycle. Convection ovens reduce this vacillation by using a motorized fan with or without its own heating element to circulate the heated air evenly throughout the oven cavity. Should any of the ignition system components fail, the oven will either not heat at all or heat incorrectly. The component that most normally fails is the igniter. If your oven’s bake or broil burner is not working, remove any covers or shields and check whether or not the burner’s igniter is glowing. If the igniter is glowing but the burner has not been lit after 90 seconds, there is a high probability that the igniter has become weaker and is not able to draw the proper amps to open the safety valve in order to light the burner. In this case, the igniter needs to be replaced. If the igniter is not glowing, you should test the igniter as well as the safety valve to ascertain if one them has stopped functioning. If one or both of the burners still do not work, the oven is overheating or the temperature is off by more than 40 degrees Fahrenheit once preheated, the oven control is probably faulty. If your oven has a switch-based control with a thermostat and sensing valve, the entire assembly will need to be replaced. If your oven has an electronic control, the oven sensor can be tested to determine whether or not the sensor or control board is the source of the problem.