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Signs Your Furnace Needs Repair

CM Heating - Signs your furnace needs repair

Nothing is quite as nice to have in the winter months as a working furnace in the home. And yes, “working” here is the keyword because when the furnace breaks down, you’ll find yourself scrambling to get it repaired.

The panic and the stress of the moment can be far more manageable if you learn to identify the signs of a needed repair before your furnace breaks down. Therefore, we dedicate this blog to unveiling these signs to help you get professional help faster before you end up with a broken furnace.

Read on to get the scoop on furnace repair signs from the best heating techs in town. 

Top 7 Signs Your Furnace Needs Repair

Rising Energy Bills

Inconsistent Heating

Strange Noises

Pilot Light Issues

Frequent Cycling

Poor Air Quality

Age of the Furnace

Rising Energy Bills

Even the most minor malfunction in a furnace can lead to increased energy consumption, which in turn will increase your energy bills. Malfunctions or neglected repairs cause the furnace to work harder and use more energy.

Tips for Monitoring Energy Bills

Monitoring your energy bills can help you identify potential issues with your furnace or HVAC system. Here are our tips for doing so: 

  • Regularly check and compare bills
  • Use online tools or apps provided by the utility company to monitor energy usage in real-time
  • Look for sudden spies in kWh usage
  • Compare yearly usage 

There is a significant link between energy efficiency and furnace functionality. If your furnace isn’t efficient, it will drive up your energy costs. If you identify inefficiencies in the operation of your furnace, we strongly recommend contacting a furnace repair tech for professional assistance. 

Inconsistent Heating

When the furnace distributes heat unevenly throughout the house, you have a clue that something may be wrong with it. This inconsistent heating is easy to discover as you will soon identify cold spots and rooms that are colder than others. 

Inconsistent heating is caused by a variety of issues that must be investigated, including: 

  • Thermostat issues
  • Airflow problems
  • Dirty or clogged filters
  • Ductwork issues
  • System imbalance
  • Incorrect system sizing
  • Thermostat placement
  • Malfunctioning zone control systems
  • Insufficient insulation
  • Closed or blocked radiators


The issue of inconsistent heating is not as simple to figure out. But, with the help of a professional repair tech, your furnace will be restored to normal. 

Strange Noises

Sometimes the furnace creates unusual noises that are worth paying attention to as they indicate a needed repair. Below are some sounds to keep an ear out for so that you can address them properly. 

Banging or Popping

A loud banging or popping noise may indicate that the ductwork is expanding and contracting due to temperature changes. This could also suggest that there’s an ignition delay, causing gas buildup and a sudden ignition when it occurs.

Screeching or Squealing

High-pitched screeching or squealing sounds often point to an issue with the blower motor or the belt that connects the motor to the blower. A loose or worn-out belt may require tightening or replacement.


Rattling noises can result from loose components, such as screws, bolts, or panels within the furnace. Check for any visibly loose parts and tighten them appropriately.


Clicking sounds during startup and shutdown is normal, but persistent or loud clicking may indicate an issue with the ignition system, such as a faulty flame sensor or igniter.

You also want to keep an ear out for any humming, buzzing, booming, grinding, or dripping as these can also be a clue that a furnace repair is needed. 

Pilot Light Issues

The pilot light of a furnace plays a key role in the whole system as it serves as the ignition source for the furnace. When the thermostat signals the heating system to heat, the pilot light will light up to ignite the main burner of the furnace. 

Watch out for these signs of pilot light issues: 

  • The light won’t stay lit
  • The light is weak or the flame is flickering
  • The light is yellow or orange (it should be mostly blue with a small yellow tip)
  • The ignition is delayed 
  • The pilot light goes out when the furnace turns off 
  • There is difficulty lighting the pilot
  • The pilot assembly has an accumulation of rust or corrosion

Frequent Cycling

Sometimes signs of a needed furnace repair present themselves in the form of frequent cycling of the furnace. Frequent cycling is when the furnace runs for a short while and then shuts off. The only reason a furnace should turn off is when the temperatures have reached your desired settings. If this occurs before the needed temperatures are achieved, there may be an issue with the furnace. 

Poor Air Quality

The function of a furnace is directly linked to the quality of your indoor air. Malfunctions in the furnace can hurt the circulation, filtration, or humidity control of the air. You will begin to notice larger accumulations of dust, mugginess, or other debris floating in the air when the furnace is malfunctioning. If this occurs, we encourage you to reach out to a furnace repair tech for help in resolving the issues. 

Age of the Furnace

As the furnace ages, the normal wear and tear of the unit will require more repairs. Normally, furnaces are expected to last about 15-20 years, depending on the level of maintenance they get throughout their lifetime.  

With the age of the furnace, you will notice issues like decreased energy efficiency, excessive wear on key parts, and poor indoor air quality. You may also notice an increase in the frequency and cost of repairs. 

Call Now for the Best Oil Furnace Repair

If you notice one or two of these signs of repair in your furnace, we encourage you to have the issues looked at by a professional before the furnace breaks down completely. 

Contact CM Heating & Cooling today for high-quality, efficient repairs, and stay warm all winter long!

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