Thermocouple Function On Gas Patio Heaters
The latest gas patio heaters use multifunctional controls incorporating a thermocouple linked to an electromagnetic valve. A thermoelectric gas valve used operate via a solenoid valve, instead of electric operation it is heated via a thermocouple.
Thermocouple output is sufficient to hold the gas valve open when operating normally. To lift the valve from its seating a manual valve is required. By turning the patio heater control valve the gas will enter the pilot to allow the piezo ignitor spark to light the pilot. The pilot light will energise the electromagnetic unit to open the gas control valve.
A thermocouple measures temperature using 2 different metal wires joined on the ends. The tip measures the heat whilst the other end is at a fixed temperature. A current is generated in the wire (thermoelectric) the voltage can be measured in millivolt range via a multimeter set.
The latest EC legislation changed the gas control valve to reduce the pilot flame and the latest technology will use a pulse pilot for the control. These patio heaters are much faster to light but will need air purged when changing cylinders.
Patio heaters that fails to open the gas chamber or extinguishes the pilot when the gas control knob is turned to full could be caused by a worn thermocouple. It is worth checking the electromagnetic valve when replacing a thermocouple if required.
For more information read patio heaters guide to problem solving
page, before making any repair please read through, it will save time and money before you start.
To order a new patio heater thermocouple always remove the old one from the burner to compare online before placing an order. Replacement thermocouples can be found on patio heaters spares see, thermocouple for domestic burners
and thermocouple for commercial patio heaters
A generic patio heater may have a slightly different fitting within the burner, the basic function will still be same but connected using different components.
© 2003/13 Urban Industry Limited