How to Troubleshoot an Ignitor Grill on a Thermos

Close the cut-off valve on the gas tank connected to your Thermos grill, turning the knob on the tank top clockwise.

Press the red ignitor button on the front panel of your Thermos grill while looking under the grill at the ignition plug mounted beneath the burner. As the button depresses, you should see a yellow spark arc upward toward the burner and hear a sharp click as the button is pushed. If not, continue troubleshooting.

Push the wire firmly onto the clip on the bottom of the spark plug and the back of the ignitor button to ensure you have a good connection, then press the button again.

Unscrew the spark plug from the bottom of the grill by removing the retainer nut with pliers, taking care not to damage the wire or the clip on the plug.

Rub steel wool on the tip of the plug to remove any corrosion or grease from grill drippings. When the tip is shiny, reinstall it in the bottom of the grill and tighten the retainer nut with pliers.

Press the ignitor button again. If the ignitor fails to produce a spark or you do not hear a clicking sound as the button is pushed, the ignitor is likely worn out and should be replaced. Write down the model number of your particular Thermos grill to purchase a replacement part from a hardware store or to order a part from Thermos. Find ordering information the Resource section below.