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 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. 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 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 and patio heaters top repair tips pages. Before making any repair please read through the help pages, it will save time and money before you start. To order a thermocouple it's best get the old one out of your burner and compare online before placing an order. Replacement thermocouples can be found on patio heaters spares see, thermocouple for domestic patio heaters and thermocouple for commercial patio heaters. A generic heater may have a slightly different fitting but the basic function will still be same but connected using different components. © 2003-2010 Urban Industry Limited <Return to spare parts