Furnace Gas Valve Shuts Off

Sometimes if the flame sensor is dirty it will fail to detect a flame.

Furnace gas valve shuts off.

A flame sensor lets your system know there s a flame when the gas valve is open. If it does not detect a flame it shuts the gas valve. 2006 irc g2420 1 2 prohibited locations says shut off valves are prohibited in concealed locations and g2420 5 says shut off valves have to be separate from the appliance. If there isn t a flame the sensor will shut off the gas valve to keep the gas from getting into your house.

My rheem home gas furnace gas valve chatters off and on is very noisy and wakes me up i replaced the thermostat answered by a verified hvac technician. Also can the furnace be changed out without removing the valve or does the valve not fit through the knock out in the cabinet. And one well lit match could cause an explosion. These two switches are safety switches and they are in series which means power passes from one to the other and then to the module board which sends power to the gas valve and the igniter which does the sparking and ignites the gas.

That thermo switch opens if the furnace gets too hot and shuts down the gas. As a result this cuts off the supply of gas to the pilot light. If your furnace shuts off too often you could have a corroded or dirty flame sensor. You will occasionally have to replace the gas shut off valve or thermocouple as it is also called.

Ultimately the thermocouple acts as a safety mechanism that prevents gas buildup within the home. If the furnace shuts down normally and then later the thermostat calls for more heat the blower should start as soon as the thermostat closes then after a short delay the igniter will spark causing a snapping sound usually three times before it gives up. If the flame sensor is dirty or has become corroded the flame won t. Try cleaning the flame sensor with a fine abrasive pad.

A 24 vac transformer or the thermopile powers the main valve. They are designed to close the gas supply if the pilot light flame does not come on or if it is extinguished for some reason. A gas shut off valve can be found in most modern gas appliances. If i shut off the power to the furnace and turn it back on it starts up and.

Well the flame sensor rod is a safety device designed to detect a flame in your furnace burners. Ntrol board will shut off voltage to the gas valve to prevent the furnace from heating. Without adequate heating of the thermocouple or thermopile the furnace gas valve closes. We use cookies to give you the best possible experience on our website.