Understanding How a Gas Cooktop Operates

Gas cooktops vary in appearance, but basic functionality is the same

Whether you have a Jenn-Air, Bosch, or a KitchenAid cooktop, it doesn’t matter; basic functionality is the same for all makes and models of gas cooktops.
Have you ever gone out to the kitchen to cook something only to discover that after you turned one of the burner controls to ignite one of the burners, that it either produced a continuous or intermittent spark but did not produce a flame? Or perhaps you turned the burner on and it did not spark at all?
Before we address those common problems, let’s take a look at how your gas cooktop operates.

How a Gas Cooktop Operates

The following describes what is known as an electronic ignition system.
  • Most newer cooktop models come equipped with four or five burners. Each burner has a corresponding surface burner knob that controls a burner valve.
  • When the knob is turned to the lite position, the burner valve opens, releasing gas to flow to the manifold.
  • The gas then travels through a burner tube and is directed into the venturi where it combines with oxygen to create a proper mixture of gas and air necessary for combustion.
  • At the same time, the spark switch closes and allows 120 volts of alternating current (AC) to travel to the spark module that produces high voltage pulses to ALL electrodes.
  • The electrical pulses cause a spark to occur between the electrode and the grounded burner cap.
  • At this point, the gas and air mixture at the burner head fires up. A blue flame is produced, and the cooking can begin.
But what if there is no flame?

Why Cooktop Burners Won’t Ignite

The following addresses three common problems that occur because there is a break in continuity in the electronic ignition system.
  • If the cooktop electrodes are sparking continuously when you turn the knob to the lite position, one or more switches have probably shorted out.
  • More than likely, the short was caused by liquid boiling over and splashing into one of the switches. Unplug the cooktop and wait 24 hours for the switch to dry.
  • If the electrode is still sparking nonstop, then one or more of the switches has failed and should be replaced.
  • If the electrode spark is erratic and irregular, suspect the spark module and replace it.
  • If one or more electrodes fail to spark at all, suspect the cause to be a defective switch that prevents voltage from even reaching the spark module.
  • Finally, inspect each electrode for cracks or any other visible damage.
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