Common Furnace Problems and How to Fix Them

A good furnace keeps your home warm while helping you avoid sudden breakdowns and expensive repairs. However, even well-maintained furnaces can run into issues. In this guide, we’ll walk you through some common furnace problems and how to fix them, so you can stay cozy this winter without stress.

As winter approaches, making sure your furnace works well becomes even more of a priority. Whether your furnace is making strange noises or just not heating up, these tips can help.

Why Furnaces Stop Blowing Warm Air

One of the most annoying problems with furnaces is when they run but don’t produce warm air. If you notice your furnace blowing cold air, it’s important to address the issue quickly to avoid bigger problems down the line.

Signs Your Furnace May Need Attention

Thermostat Not Working Right

Sometimes, the thermostat isn’t set correctly, or it may just be malfunctioning. The thermostat acts as the “brain” of your furnace, telling it when to start and stop heating. If it’s set to “on” instead of “auto,” the fan may keep blowing, even when the furnace isn’t actively heating.

• Solution: First, check that the thermostat is set to “auto” so it only blows air when heating. If that doesn’t help, try replacing the batteries or rechecking the settings. In some cases, if your thermostat is outdated or defective, it may be time to consider an upgrade to a programmable or smart thermostat for better control.

Dirty Air Filters

Clogged air filters block airflow, causing the furnace to overheat and shut off too soon. When the furnace overheats, it often triggers a safety switch that shuts down heating temporarily to prevent damage. This means you may feel cool air instead of warm air.

• Solution: To prevent overheating, change your air filters every 1–3 months, especially in winter when the furnace is used more often. Clean filters help air flow smoothly, keeping the system efficient and avoiding unexpected shutdowns.

Pilot Light or Ignition Problems

If the pilot light goes out or the ignition system fails, your furnace won’t be able to heat the air. The pilot light or ignition is what sparks the heating process, and without it, the furnace can’t produce warm air. This is more common in older furnaces or during particularly cold weather.

• Solution: For furnaces with a pilot light, follow your manufacturer’s instructions to safely relight it. For electronic ignition systems, which are common in newer furnaces, you may need a professional repair to restore proper function.

Blocked Air Ducts

Blocked air ducts prevent warm air from circulating through your home. Ducts are responsible for distributing heated air throughout the house, so if they’re blocked or dirty, the airflow is restricted. This can lead to hot and cold spots in different rooms.

• Solution: Look for visible blockages in the ducts and clean them as needed. Regular duct cleaning can improve both airflow and air quality, making your heating system work more effectively. For thorough cleaning, you might want to consider a professional duct cleaning service, especially if you notice excessive dust or allergies in your household.

With these steps, you can identify and resolve common furnace issues, keeping your home comfortable and your system in top shape.

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Why Is My Furnace So Noisy?

If you’re hearing strange or loud noises from your furnace, it could be a sign that something’s wrong. While some sounds are normal, like a soft hum during operation, others can signal underlying problems that may need attention. Ignoring these sounds could lead to bigger, more expensive repairs down the road.

Common Furnace Noises & What They Mean

Banging or Popping

This noise usually happens when there’s a delay in ignition. Gas can build up in the furnace, and when it finally ignites, you’ll hear a loud bang or pop as the gas combusts. This issue is most common in older furnaces or systems that haven’t been regularly maintained.

• Solution: A delayed ignition can be dangerous, as it may damage your furnace or even create a fire hazard. It’s best to call a professional HVAC technician from Wilson’s Refrigeration and Air to inspect the furnace and make necessary adjustments. Regular maintenance can help prevent gas buildup by ensuring all components are clean and functioning properly.

Squealing or Screeching

High-pitched squealing or screeching noises often mean that the blower motor belts or bearings are worn out. These components are essential for the fan’s smooth operation, helping to circulate air through the system. Over time, the belts can become loose or worn, while the bearings may lose lubrication, causing friction and noise.

• Solution: In many cases, the belts or bearings need to be lubricated or replaced. If left unchecked, worn belts and bearings can lead to more serious damage to the blower motor, resulting in a costly repair. Routine maintenance helps keep these parts in good shape, preventing excessive wear and tear.

Rattling or Vibrating

Rattling or vibrating sounds often indicate that something is loose inside the furnace, such as screws, panels, or other small components. This may happen if parts have shifted over time or were not properly tightened during previous repairs.

• Solution: Start by checking the furnace panels and tightening any loose screws or bolts you can find. If the rattling persists, it’s wise to have a technician inspect the furnace to locate and secure any other loose parts. Ignoring a rattling furnace can cause damage as loose components create wear on other parts.

Loud Humming

A soft humming sound during furnace operation is generally normal. However, if the humming grows louder, it may be due to electrical issues, such as a failing blower motor capacitor or a transformer problem. Since the furnace relies on electrical parts to operate, problems in this area can lead to poor performance or eventual breakdowns.

• Solution: Electrical problems can be tricky and potentially dangerous, so it’s best to contact an HVAC professional. The technician can diagnose if the noise is related to a capacitor, transformer, or another electrical part and make necessary repairs. Regular inspections help ensure all electrical components are functioning safely and efficiently.

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How to Avoid Furnace Breakdowns

Preventive care can help you avoid expensive repairs and keep your home warm all winter long! Here’s how you can reduce the chance of furnace breakdowns:

1. Schedule Regular Maintenance: Regular inspections can catch problems early. Wilson’s Refrigeration and Air offers maintenance agreements that include seasonal checkups to keep your furnace running smoothly.
2. Change Air Filters Often: Clogged filters are one of the main causes of furnace problems. Change your filters monthly during the heating season to improve airflow and help your furnace last longer.
3. Check Thermostat Settings: Make sure your thermostat is set to a consistent temperature. Smart thermostats can help you save energy and prevent your furnace from working too hard.
4. Inspect and Clean Vents: Dirty or blocked vents restrict airflow and make your furnace work harder. Regularly check and clean your vents to keep them clear.
5. Seal Duct Leaks: Leaky ducts let warm air escape, forcing your furnace to work harder. Have a professional check your ductwork for leaks and seal them if necessary.

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Furnace Troubleshooting for Businesses

For business owners, a broken furnace can mean uncomfortable conditions for employees and customers, as well as higher energy bills. If you manage a commercial property, these tips can help you avoid expensive repairs and downtime:

• Temperature Fluctuations: Uneven temperatures in different areas of the building could be due to incorrect thermostat settings or airflow problems.
• Frequent Cycling: If your furnace turns on and off too often, it could be because of a faulty thermostat or an oversized unit.
• Noisy Operation: Commercial furnaces can get loud if there’s a broken blower motor or loose parts.

If you’re experiencing any of these issues, don’t wait for them to get worse. Reach out to Wilson’s Refrigeration & Air for professional furnace maintenance, installations, and repairs to keep your business running smoothly.

Our experienced technicians specialize in diagnosing and fixing commercial furnace problems quickly, ensuring a comfortable and efficient environment for your employees and customers.

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Schedule Your Furnace Maintenance Service Today

Keeping your furnace in good shape is important to ensure your home or business stays comfortable throughout the winter. By catching common problems early, you can avoid expensive repairs and extend the life of your furnace.

For professional furnace repair and maintenance, contact Wilson’s Refrigeration and Air today. Our team is ready to keep your heating system running smoothly, whether you’re a homeowner or a business owner.

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