Skip to content

5 Possible Reasons Why Your Furnace is Making Noises


Share This Post

Modern furnaces are designed to operate quietly, but if you hear rattling, screeching, or banging coming from your furnace, it is a sign that something is wrong. It is important to figure out what is causing the noise to determine if the issue is serious or not. 

The noises may be your furnace trying to tell you something is wrong and could be hazardous. Finding the noise source and addressing the problem will help ensure your furnace continues to run efficiently and safely.

Let’s look at some of the possible causes of your furnace noises.

1) Blower Motor

The blower motor is the fan that circulates air through your ducts and into your home. If you hear a loud rattling sound coming from your furnace, it could be a sign that the blower motor is going bad. The motor may need to be replaced, or the fan blades may need to be cleaned or adjusted.

To ensure that your furnace works optimally, it is important to keep the blower motor well-lubricated. If there is not enough oil in the motor, it can cause harm to the entire furnace system.

2) Duct Issues

Ducts are the pathways that allow air from the furnace to flow throughout your home. If there are any blockages or leaks in the ducts, it can cause a decrease in airflow, making the furnace less efficient.

In order to prevent this from happening, it is important to have your ducts inspected and cleaned regularly. This will help to ensure that your furnace runs at its highest efficiency.

3) Heat Exchanger Breaking Down

The heat exchanger is an important component of your furnace. It is responsible for transferring heat from the furnace to the air that is being circulated throughout your home.

If the heat exchanger is beginning to break down, it can cause the furnace to become less efficient and may even lead to the furnace breaking down completely.

4) Dirty Burners

If you have just turned on your furnace and you hear a loud boom or bang, similar to an explosion, this is an indication that your furnace burners may be dirty. This can cause a delayed ignition, which is hazardous and should be addressed immediately.

The burners in your furnace are responsible for providing the fuel necessary to generate the heat that is circulated throughout your home. If the burners become dirty and clogged, it can cause the furnace to become less efficient and may even lead to a complete breakdown of the unit.

5) Dirty Furnace Filter

The high-pitched sound that sometimes emits from your furnace may be caused by an obstructed air filter. This could be due to an accumulation of dust, pet hair, and other debris that is blocking the airflow, causing the air to whistle as it is forced through.

You can easily take care of noise problems yourself with no large expense. If you have disposable filters, get a new one and replace the existing one. Alternatively, if you have a permanent filter, make sure to clean it.


Furnace making noises can be caused by various reasons ranging from normal operation to more serious underlying problems. The most common causes of noisy furnaces are air filters, blower fans, burners, and ignitions.

If you think you might have furnace issues, Climate Experts can help you out. We offer furnace repair in Pickering to ensure your systems are running properly and thoroughly. Get in touch with us today to get started.

More To Explore