A furnace fan that does not shut off may cause harm to the entire heating system in the home. A couple of simple steps can help check to see if repairs can be completed at home or if professional help is required. Resetting the thermostat, clearing any clogs and replacing the filter if worn or damaged are all easy fixes for basic problems. If these do not help, it is best to get a professional opinion./
Make sure the problem does not lie with the thermostat being set to "on," which means the fan operates continuously. If it is, try resetting the thermostat to see if that solves the problem.
Look for any clogs in the filter. A clogged filter may cause severe damage to the limit switch. The limit switch senses the temperature inside the furnace, and it shuts off the fire when the temperature becomes too high as a safety, only allowing it to come back on once it has cooled sufficiently. Trying to fix the limit switch rather than replacing it may cause safety issues.
Check and change the filter frequently to reduce energy costs, reduce potential damage to the furnace and keep the air in the house clean. When a filter becomes too clogged, it restricts the air flow through the furnace, so the furnace works too hard to move the heat away. Filter pieces may also get caught in the blower wheel and need to be removed.
The blower fan, sometimes referred to as just a blower or fan, is used to circulate the hot air that is created by a furnace. All types of forced hot air furnaces come equipped with one.Full Answer >
When working on an electrical furnace fan, note it has sharp blades that can seriously injure you if you are inattentive. Also, because it is connected to wires and the furnace, there is a risk of an electrical shock. Turn off the power to the furnace or the blower fan.Full Answer >
Most home furnaces are forced air, which means cold air is heated by a fuel source, passed through a heat exchanger and then directed into the home via heating ducts. As warm air circulates in the structure, cooler air is pulled back into the furnace through cold-air return vents.Full Answer >
The most efficient furnace for a large home is a direct-vent furnace using propane or natural gas, according to Consumer Reports. Modern gas furnace designs can achieve average fuel use efficiencies of 95 percent, while oil furnaces achieve a maximum of around 90 percent.Full Answer >