How to Troubleshoot a Furnace: 10 Common Problems and Solutions

As homeowners in St. Catharines, ON, we understand that the bitter cold of winter can bring its fair share of challenges, especially when it comes to keeping your home warm and cozy. When your furnace starts acting up or refuses to turn on, it can be a cause for concern. But worry not, because, at Niagara Home Heating, we’ve been your trusted HVAC partner for years, providing top-notch heating repair in St. Catharines, ON to ensure your family’s comfort.

How to Check Thermostat Settings on Your Furnace

One of the most common reasons for heating issues in your home can be traced back to your thermostat. Before you reach out for professional help, it’s essential to ensure that your thermostat settings are correctly configured. Here’s a quick guide to help you:

  • Check the Temperature Setting: Ensure that the temperature on your thermostat is set to a level that should activate the furnace. Make sure it’s not accidentally set too low.
  • Switch to “Heat” Mode: Confirm that your thermostat is in the “heat” mode. Sometimes, it might be set to “cool” during the transition seasons, leading to cold indoor temperatures.
  • Replace the Batteries: If your thermostat uses batteries, it’s a good idea to replace them if the display is dim or unresponsive.

Identifying and Replacing Faulty Parts in Your Furnace

If your thermostat is not the culprit, it’s time to delve deeper into your furnace. Identifying and replacing faulty parts is a crucial aspect of heating repair. Here are some common components you might need to inspect or replace:

  • Pilot Light: Check if the pilot light is lit. If it’s out, you may need to relight it following the manufacturer’s instructions.
  • Burner and Ignition System: Inspect the burner and ignition system for any visible issues or damage. Sometimes, they may require professional servicing.
  • Furnace Filter: A clogged or dirty filter can impede airflow, causing your furnace to work harder. Regularly changing or cleaning the filter can make a significant difference in your system’s efficiency.

How to Fix a Blower Motor That Won't Start or Keep Running

The blower motor in your furnace is responsible for circulating warm air throughout your home. If it fails to start or stops running, your comfort will be compromised. Here’s what you can do:

  • Check Power Supply: Ensure the power supply to the blower motor is intact. Sometimes, a tripped breaker or a blown fuse may be the cause.
  • Inspect the Capacitor: If the blower motor doesn’t start, the capacitor might be faulty. A professional technician should replace it.
  • Lubricate Bearings: If your blower motor is making unusual noises, it might need lubrication. Use a proper lubricant or consult a technician.

Troubleshooting Strange Noises Coming from Your Furnace

Unusual noises emanating from your furnace can be quite unsettling. Addressing these noises promptly can prevent further damage. Common furnace noises and their potential causes include:

  • Rattling or Clanking: Loose or broken parts in your furnace, such as screws or blower wheel, might be causing these noises.
  • Screeching or Squealing: These sounds may indicate issues with the blower motor or the belt connected to it.
  • Booming or Popping: This could be due to delayed ignition or dirty burners. Cleaning or adjusting the burners may resolve this problem.

What to do if Your Furnace Isn't Turning On

When your furnace refuses to turn on, it’s a major concern, especially during the cold months. Before you contact us at Niagara Home Heating in St. Catharines, ON, try these troubleshooting steps:


  • Check the Thermostat: Make sure the thermostat settings are correct.
  • Inspect the Circuit Breaker: Ensure the circuit breaker for your furnace is not tripped.
  • Check the Gas Supply: Verify that the gas supply is on and that the valve leading to your furnace is open.

What to Do if You Have No Heat but Air is Still Blowing

If your furnace is running, but the air blowing from the vents is cold, it can be frustrating. Here are some steps to take to avoid furnace repair in St. Catharines, ON:

  • Check the Thermostat Fan Setting: Make sure the thermostat is set to “auto” instead of “on” to avoid continuous air circulation.
  • Inspect the Heat Exchanger: A cracked or damaged heat exchanger can cause warm air to escape. This is a serious issue that requires professional attention.

Checking for Air Duct Obstructions in Your Furnace

Your heating system’s efficiency can be compromised if there are obstructions in your air ducts. To ensure a consistent flow of warm air throughout your home, check for the following:

  • Inspect Air Vents: Ensure that furniture or drapes are not blocking air vents.
  • Clean Ducts: Over time, dust and debris can accumulate in your ductwork, reducing airflow. Consider professional duct cleaning if needed.

Inspecting and Cleaning the Filter in Your Furnace

Regular maintenance of your furnace filter is vital for efficient heating. Here’s how to inspect and clean it:

  • Locate the Filter: Find the filter location in your furnace system, typically in the return air duct.
  • Remove and Inspect: Take out the filter and inspect it for dirt and clogs.
  • Clean or Replace: Depending on the type of filter, either clean it or replace it as needed.

Troubleshooting Uneven Heating in Different Rooms

Uneven heating can lead to discomfort in various areas of your home. Here are some steps to address this issue:

  • Adjust Vents: Check the vents in different rooms and ensure they are open and unblocked.
  • Balance the System: Consult a professional technician to balance your heating system, ensuring even distribution of warm air.

Dealing with Strange Noises or Smells

Furnace-related noises and odors should never be ignored. If you encounter strange smells or sounds, it’s crucial to take immediate action:

  • Burning Smell: A burning odor can indicate an electrical issue or overheating. Turn off your furnace and contact a professional.
  • Rotten Egg Smell: If you detect a rotten egg odor, it could be a gas leak. Leave your home immediately and call your gas company and a technician.

In conclusion, maintaining a well-functioning furnace is essential for your home’s comfort during the harsh Canadian winters. At Niagara Home Heating, we are dedicated to keeping your heating system in prime condition. By following the guidelines outlined in this blog, you can troubleshoot common issues and ensure your family stays warm and cozy all season long. Remember, we’re here to provide professional heating repair in St. Catharines, ON whenever you need us. Stay warm and comfortable with Niagara Home Heating!