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

Your furnace keeps your family warm during the harsh winter months, so it’s disconcerting when something is wrong. One frequent issue is a furnace that endlessly switches on and turns off all the time. This problem is called short cycling. It strains equipment and could lead to pricey repairs or even premature replacement.

Short cycling can happen for varying reasons. Before you request furnace repair, consider the likely causes and how to resolve the situation.

1. Filthy Air Filter

The HVAC filter catches airborne dust, hair and other substances that could cause problems for furnace. If you don’t change the filter often enough, it can eventually be filthy and block the airflow. When this takes place, a safety device switches off the furnace to stop getting too hot. Pull Out the filter, and if it’s dirty, replace it. Going forward, get a new filter every 30 to 90 days to stop your furnace from short cycling.

2. Clogged Air Vents

A dirty filter isn’t the only issue that can reduce airflow and overheat your furnace. Walk around your home and be on the lookout for for closed or obstructed air vents. For proper system balance and performance, keep all registers open, even in unused rooms.

3. Dirty Blower Wheel

The furnace blower has blades that distribute air through the ductwork. If they are caked with dirt, the air won’t flow right, creating overheating and short cycling. Frequently putting in a new the filter is the best approach to prevent a dirty blower wheel. If the blades are already dirty, schedule furnace maintenance to have them cleaned.

4. Faulty Thermostat

Inspect your thermostat next. This is the cortex of your HVAC system and tells the furnace what to do. Ensure the thermostat is on heating mode and auto fan with the desired temperature shown on the screen. Try putting in new batteries. Also, check whether the thermostat is in bright sunlight or near a heat source that could affect the temperature reading. If you use a smart thermostat, go to the manufacturer’s site for troubleshooting guides.

5. Soot-Covered Flame Sensor

The flame sensor turns off the gas valve when no burner flame is present. The sensor can’t find the flame if it’s sooty, so the gas turns off sooner and the furnace turns off. Leave the job of cleaning a dirty flame sensor to a professional like Strogen's Service Experts.

6. Oversized Furnace

When it includes HVAC equipment, oversized isn’t always right. A larger system adds warmth to your residence too rapidly, causing unpleasant temperature changes and short cycling. The only way to take care of this issue is to request new furnace installation.

If you try the fixes we went over here and you’re still having issues, it’s time to call in the professionals at Strogen's Service Experts. We’ll take a look at the situation, diagnose the cause, and do the necessary work. Our goal is to restore 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 request HVAC repair, reach us at 603-923-4570 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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