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Five Common Causes Behind A Short-Cycling Furnace

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When temperatures drop, the last thing you want to discover is that your furnace system isn't functioning correctly. One frequent complaint from chilly homeowners is that their furnace starts and stops again frequently without ever reaching the right temperature. This is a process known as short cycling, and it can cause serious damage to your furnace if left unchecked. Although you may need to call in a furnace repair specialist to fix the issue, checking these five common causes of short cycling can be all you need to identify the problem. 

Dirty Air Filters

If it has been a while since you swapped out your air filters, your first course of action should be to check them. A dirty filter blocks airflow within the heating system, trapping hot air and confusing the furnace's sensors. The furnace then begins to short cycle in an attempt to meet your house's demand for heat without frying its own components. Cleaning or changing your air filters can be all it takes to fix your heating troubles. 

Blocked Ventilation

Similarly, once the hot air is carried through your house's ducts, it needs to be able to flow into your rooms without obstruction. Remove any furniture, objects or filters that could be blocking the heating vents in your home and try the system again to see if the issue has been corrected. One covered vent is usually not enough to cause short cycling, but it could be dramatically reducing the heating efficiency of your home. 

Malfunctioning Thermostat

Another common culprit behind short cycling is a thermostat that is broken, using the wrong settings or simply sitting too close to another source of heat. Since the thermostat typically dictates when a furnace turns on or off, any interruption or irregularity in the signal can make the whole system go haywire. Have a professional evaluate your thermometer for signs that it needs to be replaced. 

Improper Duct Sizing

Newer furnace systems that suffer from short cycling are often the result of poor installation, when contractors pair a furnace with ducts that are too large or small for a house's heating requirements. You should rely on the opinion of a certified heating contractor to reevaluate your system and determine whether or not your home's ducts need to be refitted to solve the short cycling permanently. 

Damaged Furnace Components

Of course, a furnace short cycling can also mean that the furnace itself is broken. Clogged fuel lines, corroded sensors and damaged electrical wiring could all be responsible for this erratic behavior. Instead of diving into your furnace to search for the defective part on your own, it may be wiser to let an expert run tests and repair the system instead. With any luck, the problem will be easy to resolve and your home will be back up to a comfortable temperature in no time.