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dacor

Dacor Cooktop keeps Sparking


Model #PGM365-1, this five burner gas cooktopicon was working correctly with the exception of the right front burner. When this burner was lit, the ingiter would stop sparking for a moment, then continue to spark as long as the burner valve was on. The rest of the burners would spark properly and stop once the burner was lit, so the problem was clearly limited to the one burner.

Gas cooktops generally use a spark type ignition source which consists of a high voltage spark module, and an electrode located near the burner. The electrode acts much like a spark plug in a gas engine to produce a high voltage arc of electricity which will cause the gas and air mixture from the burner to combust. The spark module is the cooktop part that produces the high voltage used by the electrode, but also monitors the electrode in case the flame were to be extinguished while the gas valve was still in the on position. This safety relight system is not used on all gas cooktops, but is becoming more common.

Ignition failures can usually be limited to either the module itself, an igniter electrode, or a control switch on the valve shaft. These switches are used to provide voltage to the module which them steps it up before being output to the electrode. Since the other burners were working properly, and even the failing burner would light, I knew the spark module was working properly along with the control switches. This leaves the electrode as the likely cause of this problem.

When looking at the electrode, I could see the spark jump from the electrode wire to the burner itself causing ignition. But moment later, I would again hear the clicking of the spark, but this time, the spark was not visible and sounded like it was coming from under the cooktop. Because high voltage are used, and electrical current likes to follow the path of least resistance, this was most likely a loose connection, or even a damaged wire or insulator under the burner.

I began by removing all the burners and knobs so I could remove the top of this unit. Once the inner workings were visible, I began looking at the wire harness leading to the suspect igniter, and found the insulation had been cracking. These cracks are where the voltage was arcing to the burner support under the cooktop resulting in the continuous sparking.

The mounting clip was removed from the burner base and the electrode removed from the wiring harness. A new electrodeicon was installed and connected to the burner and harness making sure the wire wasn’t touching any of the metal chassis parts. With everything put back together, and the burners back in place, I again turned the burner on, but this time, when the burner ignited, the clicking stopped, and didn’t return.

Just a troubleshooting note on igniter electrodes. If you suspect one of the electrodes is not working, it is usually possible to swap it with one on another burner to at least verify your failure.

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