6 Reasons Why Your Furnace Keeps Shutting Off and How to Resolve It 

Your furnace keeps your house comfortable during the frigid winter months, so it’s disconcerting when something is off. One routine complaint is a furnace that continuously kicks on and switches off over and over. This operating error is referred to as short cycling. It stresses equipment and could result in pricey repairs or even earlier than normal breakdowns. 

Short cycling can be caused by for a few reasons. Before you book furnace repair, read about the possible causes and how to fix the situation. 

1. Dirty Air Filter 

The HVAC filter catches airborne dust, hair and other debris that could damage the furnace. If you don’t change the filter often enough, it can eventually be dirty and reduce the airflow. When this happens, a safety feature switches off the furnace to prevent getting too hot. Inspect the filter, and if it’s dirty, replace it. From now on, replace the filter every 30 to 90 days to stop your furnace from short cycling. 

2. Obstructed Air Vents 

A dirty filter isn’t the only thing that can reduce airflow and overheat your furnace. Walk around your home and check for shut or obstructed air vents. For proper system balance and performance, keep all registers open, even in unoccupied rooms. 

3. Dirty Blower Wheel 

The furnace blower uses blades that push air through the ductwork. If they are covered in dirt, the air won’t flow properly, leading to overheating and short cycling. Regularly replacing the filter is the simplest way to avoid a dirty blower wheel. If the blades are already dirty, book furnace maintenance to have them cleaned. 

4. Faulty Thermostat 

Check your thermostat next. This is the cortex of your HVAC system and instructs the furnace on what to do. Ensure the thermostat is set to heating mode and auto fan with the desired temperature showing on the screen. Try replacing the batteries. Also, check whether the thermostat is in full sunlight or near a heat source that could impact the temperature reading. If you use a smart thermostat, check the manufacturer’s site for troubleshooting guides. 

5. Dirty Flame Sensor 

The flame sensor is responsible for turning off the gas valve when no burner flame on. The sensor can’t find the flame if it’s coated in soot, so the gas turns off too soon and the furnace shuts down. Leave the adjustment of cleaning a sooty flame sensor to an Expert like Service Experts Heating & Air Conditioning. 

6. Oversized Furnace 

When it includes HVAC equipment, bigger isn’t always better. A bigger system warms up your house too fast, creating intolerable temperature swings and short cycling. The only way to resolve this situation is to schedule new furnace installation

If you go through the resolutions we went over here and you’re still having problems, it’s time to reach the pros at Service Experts Heating & Air Conditioning. We’ll take a look at the situation, diagnose the cause, and do the necessary service. Our priority is to bring back indoor comfort, energy efficiency and dependable furnace performance for all season long. And our work is upheld by a 100% Satisfaction Guarantee for a year.* For more info about furnace short cycling, or to schedule HVAC repair, call us at 954-736-4314 now! 

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*Not applicable to the Advantage Program. See your signed Advantage Program Agreement for full details and exclusions. 100% Satisfaction Guarantee is subject to certain restrictions and limitations as set forth in the applicable Terms and Conditions. 

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