618174 Genuine Wok Burner Thermocouple for Bosch, Siemens, Neff Gas Cooktops, BSH 00618174 Flame Failure Probe

BSH thermocouple 618174, also written 00618174, is the genuine flame failure sensor for the wok burner on Bosch, Siemens and Neff gas cooktops. It sits in the flame and tells the gas tap a flame is present, so the gas keeps flowing. The other burners may use different thermocouples, so check that 618174 matches the wok position on your parts list.

Wok burner won't stay lit?

A thermocouple produces a small voltage when its tip is heated by the flame. That voltage holds open a magnet valve in the gas tap. If the flame goes out, the tip cools, the voltage drops and the magnet shuts the gas off within seconds. When the thermocouple weakens, or its tip is bent out of the flame, the burner lights while you hold the knob in but goes out as soon as you let go. Check the tip is clean and sitting in the flame, as a misplaced burner cap causes the same problem.

Part details

• Genuine BSH thermocouple, part 618174
• Also written 00618174
• For the wok burner
• Flame failure safety part for Bosch, Siemens and Neff gas cooktops

Fitting the thermocouple

This is a gas safety part, so in Australia only a licensed gas fitter should install it. Turn off the gas and isolate the power before the cooktop is lifted. The thermocouple connects to the back of the wok burner's gas tap, and its tip sits beside the burner. Once it's fitted, every burner should be tested for leaks and correct flame failure operation.

Questions about this part

How long should I hold the knob in when lighting the wok burner?

Hold it in for a few seconds after the flame lights so the thermocouple can heat up, then let go. If the burner still goes out after ten seconds or so, the thermocouple or the magnet in the gas tap is the likely fault.