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How to Troubleshoot a Furnace – Top 10 Tips

How to Troubleshoot a Furnace - Top 10 Tips

How to Troubleshoot a Furnace – Top 10 Tips 

One of the biggest challenges homeowners face in the winter is when they are forced to troubleshoot furnace issues on an already cold day. To help prepare you for another chilly season, we want to dedicate this blog to the most common furnace problems to expect and what can be done to solve them. 

  1. Dirty or Clogged Filters

  2. Lack of Maintenance

  3. Thermostat Issues

  4. Ignition or Pilot Control Problems

  5. Blower Motor Dysfunction

  6. Mechanical Wear and Tear 

  7. Cycling On and Off Too Frequently

  8. Unusual Noises

  9. Inconsistent Heating

  10. Carbon Monoxide Leaks 

It is never convenient to deal with an electric or gas heater not turning on, especially when winters are incredibly chilly. Below, we will review these common furnace problems and provide tips on what to do if your furnace goes out in your home. 

Why Is My Furnace Not Turning On?

Dirty or Clogged Filters

As furnace repair technicians, one of the most common furnace issues we come across is clogged air filters. During the fall and winter months, the furnace is used very heavily, and filters tend to accumulate dust and debris as they clean the air flowing through the system. 

To ensure clean indoor air quality, energy efficiency, and reliability, make sure that your air filters are cleaned or changed every 4 to 6 weeks. If you feel that your air filters are changed often enough, there may be a problem with the overall maintenance condition of the furnace. 

Lack of Maintenance

Regular maintenance is critical to an efficient and reliable furnace. Many parts of a furnace go bad that can be kept in excellent condition with regular maintenance and tune-ups from a furnace repair tech. 

Technicians take the time to adjust, lubricate, and clean parts of the furnace. They also inspect it for potential problems, repairing them before they grow into bigger issues. This way, you have a higher likelihood of avoiding those moments when you wake up and find that the electric or gas heater is not turning on

Thermostat Issues

During electric furnace troubleshooting, you may discover that the thermostat is behind the problems you are facing. Because the thermostat is in charge of controlling the temperatures in the home, any of its malfunctions can quickly lead to disruptions in the rest of your heating system. 

Here are common issues to expect in a thermostat: 

  • Inaccurate temperature readings
  • Electric or gas furnace not working to turn on
  • The furnace is constantly running
  • The heating system is short-cycling
  • The controls are unresponsive
  • Persistent battery issues
  • Connection problems
  • Delayed response 
  • Wiring issues
  • Sensor issues

If you believe that your thermostat is the culprit behind your gas furnace not working, reach out to Air Pros USA for help in fixing or replacing it. 

Ignition or Pilot Control Problems

Ignition control problems can be a great source of frustration for many homeowners, especially during the cold winter months. These problems occur when there are dirty or clogged components of the pilot light system or when they are worn out. Additionally, there are times when the flame sensors are improperly positioned, which causes them to be unreliable during the ignition stage of heating the home. Various gas supply problems and electrical issues can also lead to problems with the pilot control, leaving you with challenges in using your furnace effectively. 

If there’s an issue with the ignition system in your furnace, here are some things you can do:

  • Clean the ignition or pilot components
  • Inspect the thermocouple to see if it’s damaged or worn out. If so, it will need to be replaced.
  • Adjust the flame sensors so that they are correctly positioned and cleaned. Reference the manufacturer’s guide for the correct position of the flame sensors.
  • Check that the gas supply is adequate and that the gas pressure is at an appropriate level.
  • Check the electrical components to ensure that all the connections are in working condition. Make sure that nothing is damaged, Lucy, or frayed.

If cleaning and adjustments don’t resolve the issue, consider replacing faulty components like the thermocouple, pilot, assembly, or electronic ignition control. These replacements will have to be performed by a certified furnace repairing technician who specializes in these issues.

Blower Motor Dysfunction

Sometimes, furnace blower motor troubleshooting is needed because it begins to cause issues with the heat flow through the house. The blower motor plays the vital role of distributing heated air to the rest of the house, and when it’s broken, your home will not warm up as much as it should. 

Signs of a Failing Blower Motor

  • Weak airflow
  • Unusual noises
  • Inconsistent heating
  • Excessive energy consumption
  • Short cycling
  • Overheating
  • Failure to start

To fix these issues, the blower motor must be inspected for obstructions and adequately lubricated. We recommend that it is also evaluated by a professional furnace repairing technician who can test its electrical function. If need be, they will be able to repair or replace this component of the furnace. 

Mechanical Wear and Tear

As the furnace works to heat your home, it will develop the typical wear and tear in its mechanical parts. After all, this is the normal life cycle of almost anything. To get the most out of your furnace, follow these tips:

  • Invest in regular maintenance services that will ensure all parts are lubricated and aligned for proper function
  • Do not delay repairs when you suspect a problem
  • Give the furnace a break after 8-10 hours of continuous operation
  • Do not set your thermostat 10 degrees higher or lower than the temperatures outside

Cycling On and Off Too Frequently

Another problem that creates a lot of frustration in the winter is when the furnace is cycling on and off too frequently. This problem leads to a lack of warmth and comfort in the home and can be caused by any of the following: 

  • Improperly sized furnace equipment
  • Thermostat problems
  • Clogged air filters
  • Restricted airflow
  • Refrigerant issues
  • Flame sensor problems

If you want to address this issue by yourself, you can attempt to do the following: 

  • Test the thermostat to ensure it displays correct temperatures by comparing it with a different thermostat. 
  • Change your air filters regularly
  • Inspect and clear vents, registers, and ducts of any obstructions

Unfortunately, many short cycling issues stem from inside furnace components that have to be addressed by a professional. If the preliminary steps suggested above do not help fix the problem, contact an Air Pros USA brand today for assistance. 

Unusual Noises

Sometimes, you can operate a broken furnace, but you will find it making unusual sounds. These unusual sounds typically come with inconsistent performance as well. Here are the unusual sounds that typically indicate that furnace repair is needed: 

  • Banging or popping sounds
  • Screeching or squealing
  • Rumbling or booming
  • Clicking or ticking
  • Whistling or hissing
  • Rattling or vibrating 
  • Continuous running

To eliminate these sounds, we recommend visually inspecting the furnace for any loose parts or stuck debris within the unit. Carefully remove all debris and tighten any loose bolts or screws. 

Take the time to change your air filter and ensure that the thermostat is working correctly. If the noise persists, you must contact a technician for furnace repair services. 

Inconsistent Heating 

There are a handful of reasons for inconsistent heating and overall poor performance of a furnace. These issues include poor insulation, blocked or closed vents, leaky ductwork, dirty furnaces, and even inaccurate thermostat placement. Here are the suggested heating repairs for dealing with such issues: 

  • Improve insulation
  • Check and adjust vents
  • Inspect ducts for cracks, gaps, and dirt
  • Change the air filters
  • Optimize sun exposure
  • Adjust the zoning system 

Carbon Monoxide Leaks

Lastly, one of the issues why your gas furnace may not be working is because of a carbon monoxide leak. Carbon monoxide leaks are dangerous and are commonly referred to as the silent killer. It is an odorless, tasteless, and colorless leak that can lead to poisoning and flu-like symptoms. It is essential to be aware of potential carbon monoxide leaks and to be proactive in preventing them.

Avoiding Carbon Monoxide Leaks:

  • Install CO detectors
  • Invest in professional inspections on an annual basis to ensure that your gas furnace is in safe and operational condition
  • Ensure proper ventilation around the furnace
  • Make sure you know where the CO detector alarms are and that they are equipped with fresh batteries
  • Address leaks promptly
  • Consider a professional CO test

Most importantly, do not skip out on regular furnace maintenance services offered by your Air Pros USA technicians. Regular maintenance is critical to ensuring that your heating equipment remains in optimal and safe condition.

Is Your Electric or Gas Furnace Not Turning On?

If your furnace is giving you a hard time, do not delay the repairs!

Check out the list of all Air Pros USA locations to get help from our team of expert Furnace Techs in your area. 

Contact Air Pros USA technicians in FL, GA, AL, LA, TX, MS, CO, and WA today for a thorough assessment of your Furnace.


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