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Ensuring Safe and Efficient Hot Water Systems in Sydney:

Guide to Replace a Thermocouple on a Hot Water Systems in Sydney

The thermocouple refers to a thermoelectric device that turns off the gas when the pilot light is off. In a nutshell, it’s a short piece of tubing that extends from the gas controller to the pilot. The pilot end of the thermocouple and the pilot are placed alongside each other in a bracket that’s attached to the burner. When you have a hot water heater with a pilot light that can’t seem to remain lit, it’s most likely due to a faulty thermocouple.

Replacing your thermocouple should be easy. Make sure that there are no open flames from cigarettes or other sources in the area when working on a gas water heater, it might be a good idea to seek professional help. Always use a licensed gasfitter for this type of work. Plumbing specialists like Active Plumbing can provide quality and reliable services for hot water systems in Sydney to satisfy all your maintenance and repair needs. Here are some of the most important things you need to remember when replacing your hot water heater’s thermocouple.

Types of Thermocouples

  • Standard – This type is also referred to as the universal water heater thermocouple. It is located at the bottom of the gas valve and a probe on the other end fits into a holding bracket close to the pilot light. It resembles a piece of copper wire. Nearly all older water heaters and most of the newer models that feature a sealed burner compartment and a viewing window will have this type.
  • TCO – The Thermal Cut-Off style has a resettable thermal shut-off switch built into the thermocouple. The TOC switch resembles a watch battery. This type of thermocouple of the hot water systems in Sydney can only be found on newer water heater models that have sealed burner compartments.
  • TOC Non-Resettable – These thermocouples have a tiny TOC located inside the tube. They appear similar to the standard thermocouple, aside from the diameter which is larger midways of the tube. When these TOCs switch off, they will not reset and should be replaced.



Once you find the thermocouple, switch off the gas to the furnace. Then, take out the thermocouple from the control box and from where it is attached close to the pilot light. Replacement thermocouples are easily available in most supply shops and come in various standard lengths. Just have to take the thermocouple that has been removed and re-install the exact same model. If you are buying a thermocouple you might also want to have the model and serial number with you, to give to the sales assistant just in case. Installing the new thermocouple is simply a case of removal and replacement. However, in many cases, the burners will have to be removed and changed. Contact Active Plumbing for any assistance regarding any installation & maintenance of hot water systems in Sydney.

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