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What to do if your furnace is short cycling

Before the cold starts to creep in, it’s best to make a home’s furnace is running without issue. One such problem to look out for is whether the furnace is short cycling. Both a noisy and uncomfortable issue, short cycling is when the furnace is consistently turning on and off, with dramatically short periods between the on-and-off time, resulting in heat poorly circulating throughout the home. While diagnosing short cycling seems fairly straight forward, there are several different issues that could be the underlying cause, and it’s important to address the right one to ensure a home is able to maintain comfort in the cold months ahead. 

The Furnace is Too Big

It seems strange to say, but it’s entirely possible that the furnace is too big for the home it is trying to heat. When a furnace is too large, it is unable to properly regulate the amount of heat to circulate throughout the home, leading to uneven heat distribution, noticeable when certain rooms are much warmer than others. Because the heat is not properly distributed, the furnace will stop the cycle suddenly to try to reduce the heat, but then overcompensate once again when it kicks back on. The main solution to this issue is to make sure that the furnace being installed is the correct size for space by consulting with professional, reputable HVAC installers before purchasing or installing a unit. 

The Furnace is Overheating

Another potential reason for short cycling is that the furnace itself is overheating. One of the most common causes of overheating is from some form of blocked or restricted incoming airflow to the furnace — usually from a dirty air filter or a blockage in the vents. If the unit is unable to get proper airflow, the hot air in the furnace will become trapped, potentially damaging the internal electronic sensors and motors, and forcing the furnace to short cycle to try to cool down. 

It’s important that a professional inspect and resolve to overheat, as left unchecked, this issue can lead to cracks within the furnace, creating leaks of deadly carbon monoxide. Rather than risking a potential health hazard, turn off the unit at the first sign of overheating, and call a professional HVAC contractor.

The Furnace is Receiving Bad Temperature Data

This is actually an issue with the thermostat, and not with the furnace directly. If the thermostat is malfunctioning, it can send signals to the furnace to start and stop at random intervals, rather than trying to maintain a consistent temperature. Alternately, it could be possible that the thermostat is simply located in a poor location, such as directly in the path of a heat vent, or within a utility closet, preventing the thermostat from properly reading and communicating the temperature as needed. 

No matter the cause, it’s important that issues with the furnace be properly inspected and addressed by a licensed heating and cooling professional. If you are worried about the way your furnace is running or have questions about how it is cycling, reach out to the licensed experts at Duane Blanton Family Home Services. Providing quality service for over 30 years, the licensed technicians at Duane Blanton will be able to inspect, diagnose, and repair any issue that may arise with your home’s furnace. Give the professionals at Duane Blanton Family Home Services a call today, at (815) 781-2567, or schedule online using their convenient online scheduling portal


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