5 Common Furnace Problems and How to Fix Them

As the colder months approach, your furnace becomes one of the most essential appliances in your home. When it stops working properly, it can be frustrating, not to mention uncomfortable. Understanding some common furnace issues and how to address them can help prevent costly repairs or service calls. If you’re experiencing furnace problems, don’t panic – here’s a list of the five most common furnace issues and how to fix them.

Furnace Won’t Turn On

If your furnace refuses to start, it could be a simple issue like a tripped circuit breaker, a blown fuse, or a thermostat malfunction. If the system seems to be getting no power, start by checking the circuit breaker to ensure it hasn’t been tripped. Also, check if the thermostat is set correctly and the temperature is turned up.

How to fix it:

1. Reset the circuit breaker if necessary.
2. Replace blown fuses in the furnace.
3. Ensure the thermostat is working properly and set to heating mode.
4. Check the pilot light (if your system has one). If it’s out, relight it according to the manufacturer’s instructions.

If these steps don’t resolve the issue, it’s a good idea to call a professional HVAC technician to check the internal components of your furnace.

Insufficient Heat

One of the most common complaints during the winter is a furnace that is running but not producing enough heat. If your furnace isn’t warming your home as expected, there could be a few causes. The most common reasons are a dirty air filter, a faulty thermostat, or an issue with the pilot light or ignition system.

How to fix it:

1. Change or clean the air filter: A dirty filter can restrict airflow, causing the furnace to work harder and lose efficiency.
2. Check the thermostat settings: Ensure it’s set to the correct temperature and heating mode.
3. Examine the ducts: Blocked or leaky ducts can prevent warm air from reaching the rooms in your home. Seal any visible gaps or cracks.
4. Check the pilot light: If it’s out, relight it according to the manufacturer’s instructions. If the problem persists, the thermocouple may need replacing.

Regular maintenance and cleaning of your furnace can prevent this issue from occurring. If you’re unsure of how to perform these tasks, a professional HVAC technician can do the work for you.

Strange Noises

Furnaces can make various sounds during operation, but unusual noises could signal a problem. If your furnace is making grinding, rattling, banging, or whistling sounds, it’s time to investigate the cause. Common reasons for furnace noises include loose parts, a malfunctioning blower motor, or a dirty burner.

How to fix it:

1. Tighten loose parts: Inspect the furnace for any loose panels or screws and tighten them.
2. Lubricate moving parts: If the blower motor is making a grinding noise, it might need lubrication.
3. Clean the burners: Over time, dirt and debris can accumulate on the burners, causing inefficiency and odd noises. Clean the burners or have a professional do it for you.

If the noise persists, call a professional to inspect the furnace for more serious issues that may require part replacements or repairs.

Short Cycling

Short cycling refers to when the furnace turns on and off frequently in short bursts. This issue can waste energy, increase wear and tear on the system, and lead to higher heating costs. The most common causes of short cycling include a dirty air filter, overheating, or issues with the thermostat.

How to fix it:

1. Change the air filter: A dirty filter can block airflow, causing the furnace to overheat and shut off prematurely.
2. Check the thermostat: Ensure that it’s functioning properly and isn’t located in an area with drafts that could cause false readings.
3. Inspect the furnace: If the furnace is overheating, it may have a malfunctioning limit switch. Have a technician check and replace any faulty components.

Short cycling can cause long-term damage to your furnace if not addressed promptly, so it’s crucial to take action quickly if you notice the issue.

Furnace Blowing Cold Air

If your furnace is blowing cold air, the first thing to check is the thermostat settings. If the thermostat is set to cooling mode instead of heating, it will blow cold air. Another common cause is the pilot light or ignition system failing to stay lit, resulting in no heat production.

How to fix it:

1. Double-check the thermostat: Make sure it’s set to heating mode and the temperature is set higher than the room temperature.
2. Inspect the pilot light: If the pilot light is out, follow the manufacturer’s instructions to relight it. If it goes out frequently, there may be a more serious issue with the furnace.
3. Check the gas valve: Ensure the gas valve is turned on. If there’s a gas supply issue, a professional technician will need to address it.

Conclusion

A malfunctioning furnace doesn’t always require expensive repairs. Many common furnace issues can be addressed with a bit of troubleshooting and regular maintenance. However, if you’ve gone through these steps and your furnace is still experiencing problems, it’s best to call a professional HVAC technician. At Texas Air Authorities, we have over 20 years of experience serving the Dallas-Fort Worth Metroplex, and our NATE-certified technicians are available for same-day appointments. Whether you need repairs, maintenance, or a new system, we’re here to help you keep your home warm and comfortable throughout the winter months.

Call Texas Air Authorities today to schedule a service or for a free estimate!