When you turn on your furnace on a cold day, the last thing you expect is a lack of heated air flowing through your vents. A furnace can stop producing sufficient warmth for many reasons, but what can cause a furnace to stop working altogether?
We at BVS Home Experts offer some of the best heat pump installation services in Texas, along with furnace, air conditioning, and indoor air quality services. Here, we explain a few reasons a furnace could stop working correctly.
Common Reasons Your Heating System No Longer Works
Most heating systems have a 15- to 20-year lifespan if they receive routine tune-ups. Still, even a well-maintained heating unit can develop problems with frequent use. However, knowing what can cause a furnace to stop working will make it easier to identify your specific problem and take the appropriate steps to get your home the warmth and coziness you desire.
1. Clogged Air Filter
One of the most common causes of a furnace breakdown is a filthy air filter. Since the filters continuously trap airborne allergens and pollutants, they can quickly fill with debris.
Replacing your filter at least once per season is best to keep your filters from forming clogs. If you have allergies or a pet that produces dander, you might need to swap your filters once a month to keep your indoor air clean.
Replacing your furnace air filter regularly might seem simple, but it has a major impact. Clogged filters restrict airflow from the HVAC system, forcing the furnace to overwork itself. As a result of the high furnace temperatures from the extra strain on the equipment, the furnace will stop working.
2. Flipped Circuit Breaker
Sometimes, your electrical system is why your furnace no longer works. Check the circuit breaker if your heating unit doesn’t turn on. Reset all tripped breakers or switches to ensure enough electricity is flowing to the furnace to power all components.
If the problem persists, call an HVAC technician to uncover the unit’s underlying problem.
3. Malfunctioning Pilot Light Ignition Switch
Your furnace needs a functional pilot light ignition switch to ignite the burners and generate heat. The heating system can’t work if the ignition switch is damaged or malfunctioning. Common signs of a faulty ignition switch include:
- Frequent cycling
- Constant pilot light relighting
- Reduced heat from the furnace
An outdated furnace, a damaged temperature limiting switch, and a dirty air filter can each contribute to pilot light ignition switch problems. You can troubleshoot this issue by reigniting the pilot light after turning off the furnace. When you turn the unit back on, press the ignition button as well as the small red button beside it.
Stop your troubleshooting efforts if you smell gas coming from the equipment or hear a loud scraping or banging sound while trying to trigger the ignition switch. This could signify a major problem requiring an HVAC professional’s help.
4. Broken Pressure Limit Switch
A pressure limit switch is a furnace safety feature that prevents dangerous exhaust fumes from escaping the furnace and seeping inside your home. The switch can fail due to:
- A broken draft inducer motor
- A clogged condensate line
- Incorrect air intake
- Natural wear
Diagnosing and replacing faulty pressure limit switches isn’t a do-it-yourself project. Call a qualified HVAC company for furnace repair if you suspect your unit’s limit switch is why your heating system isn’t working.
5. Thermostat Problems
Many property owners overlook thermostat issues when their furnaces suddenly stop working. For example, the thermostat could be on its “cool” setting instead of “heat,” or its batteries could be dying. Wiring problems and incorrectly preprogrammed settings could also cause furnace issues.
6. Filthy Furnace Burners
It’s not unusual for furnace burners to collect dirt, grime, and soot over time. However, if the debris is excessive, it can cause problems for the burners, leading to issues with the furnace’s operations.
7. Short Cycling
When a furnace short cycles, it kicks on for about two minutes before shutting down. This process can cause premature wear on parts and put undue stress on the system. It also forces the furnace to consume extra energy, resulting in higher utility bills each month.
Many heating problems can cause the system to short cycle, such as dirty filters and restricted airflow. To address this problem, make sure you replace your filter regularly and don’t block air vents with furniture, rugs, or other items.
8. Faulty Blower Motor
Heated air stays inside the furnace after combustion heats up the heat exchanger or triggers the heating element. The blower fan and motor are responsible for pushing the warm air from the heat through air ducts to heat the house evenly. Without the blower motor, your furnace might turn on, but it won’t warm your home.
Check your blower motor by setting your thermostat to “fan only.” You should hear the fan kick on. If it does, your lack of heat isn’t coming from the blower motor.
The Importance of Furnace Maintenance
There’s more than one answer to, “What can cause a furnace to stop working?” Still, routine furnace maintenance is the best way to keep your system running smoothly all winter.
From air filter replacement to cleaning burners and flame sensors, furnace maintenance involves many steps. Booking the service at least once yearly means a qualified technician will clean the unit, assess its efficiencies, make essential repairs, and prepare it for constant winter use.
Schedule Your Consultation With Texas's Top HVAC Contractor
If you have questions like, “How much power does a furnace use?” or, “What can cause a furnace to stop working?” you can count on BVS Home Experts to have the answer. As one of the best family-owned and operated HVAC companies serving West Houston and Katy, Texas, our well-trained technicians use years of expertise and cutting-edge technology to provide comprehensive heating and cooling solutions.
Whether your home needs a new furnace or heat pump repairs, we have the expertise to do the job right the first time. Call (281) 628-2360 today to book an appointment with our BVS Home Experts crew.
