When the temperature drops, the last thing you want is for your furnace to quit on you. But if your furnace keeps shutting off, it’s more than just a comfort issue—it’s a signthat something needs attention. This problem, often called short cycling, can lead to higher energy bills, poor airflow, and extra wear on your system.
Let’s take a look at why this happens and what you can do to fix it.
Why Your Gas Furnace Keeps Shutting Off and Needs to Be Reset
1. Dirty Air Filter
One of the most common reasons a gas furnace keeps shutting off and needs to be reset is a dirty or clogged air filter. When airflow is restricted, your furnace can overheat. To protect itself, it will shut off early, before your home gets warm.
Fix:
Check your furnace filter. If it looks gray, dusty, or clogged, replace it. Most filters should be changed every 1–3 months, especially during heavy use in winter.
2. Faulty Flame Sensor
The flame sensor is a safety feature that detects whether the burner is lit. If it’s dirty or malfunctioning, it may wrongly signal that there’s no flame, causing the furnace to shut off and sometimes requiring a manual reset.
Fix:
This part can sometimes be cleaned, but if the problem persists, it may need to be replaced. It’s best to have a technician handle this for safety and proper calibration.
3. Thermostat Issues
If your thermostat is placed near a heat source or in direct sunlight, it may signal your furnace to shut off too early. Dead batteries or wiring problems can also cause communication errors between the thermostat and the furnace.
Fix:
Check your thermostat settings and battery. If it’s still acting up, call in a heating repair professional to inspect the wiring and placement.
4. Overheating or Restricted Airflow
Besides a clogged filter, other airflow problems like blocked vents or closed dampers can lead to overheating. Once the internal temperature gets too high, your system shuts down as a safety measure.
Fix:
Ensure that all vents and registers are open and unobstructed. Furniture or rugs should not cover them. A professional HVAC inspection can help identify hidden airflow issues in the ductwork.
5. Faulty Limit Switch or Control Board
If your furnace keeps shutting off frequently even after filter changes and airflow adjustments, the problem could lie in internal parts like the limit switch or control board. These parts help regulate the furnace’s operation and safety shut-off features.
Fix:
These are not DIY repairs. You’ll need a certified heating technician to diagnose and replace faulty components safely.
Don’t Ignore the Signs—Call Residential Heating and Cooling
If your gas furnace keeps shutting off, don’t wait for it to fail completely. A short-cycling furnace wastes energy, stresses your system, and leaves your home uncomfortable.
At Residential Heating and Cooling, we’ve been helping homeowners stay warm for over 30 years. Our licensed heating repair technicians can quickly diagnose and repair the issue, whether it’s a dirty filter or a failing control board.
Call us today to schedule a furnace inspection or to request emergency repairs. We’ll get your heat back up and running—fast, safe, and done right.
612 Albion Ave.
