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Warning Signs Indicating How Often You Should Clean Furnaces

Repairing Furnace

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Furnaces are essential to our homes, providing warmth and comfort during the cold winter. However, like any other appliance, furnaces require maintenance to continue running efficiently and safely over time. One of the best ways to keep your furnace in peak condition is to clean it regularly. But how do you know how often you should do this? 

In this blog post, we’ll discuss warning signs to help you determine when to clean your furnace and keep it running at its best.

1. Presence of a Musty Smell

Musty odours in the air are unpleasant and indicate that furnace cleaning should be done regularly. This is because dust, dirt, and other particles accumulate in the filter and ducts over time. This leads to blocked airflow, inefficient performance, and the growth of mould and mildew. 

To clean your furnace correctly and ensure good indoor air quality, hiring a professional is recommended to do the job right. They can then completely clean the unit’s interior, including the filter and blower assembly. 

2. Airflow Is Not as Strong as It Should Be

A decrease in airflow is often caused by dust, dirt, and debris inside the unit preventing the air from properly flowing. If you notice any signs of poor airflow, a dust buildup on the outside of the unit, or a strange smell from the vents, it’s time to have your furnace serviced and cleaned.

Poor airflow can cause an inefficient system that will cost more money to heat and cool your home and increase the risk of safety issues such as carbon monoxide poisoning. Therefore, it is essential to have your furnace inspected and cleaned at least once a year (or more if necessary) to ensure that it is running efficiently and safely. 

3. Increase in Gas Bill

It is essential to keep up with furnace maintenance, as a sudden and drastic increase in gas bills could indicate an unclean furnace. Clean furnaces improve efficiency and help save energy. As such, when your gas bill begins to take an unexpected leap, it might be time for a professional furnace cleaning. 

4. Presence of Rust

Rust indicates that the metal components of your furnace, particularly the internal components and burners, may not be adequately protected from corrosion and oxidation. Over time, this corrosion and oxidation can lead to malfunctioning, unsafe operation, and decreased efficiency. 

When rust is present in your furnace, it is essential to clean it regularly to prevent further corrosion and maintain optimal performance. 

5. Furnace Flames are Yellow

This is due to a buildup of dust and debris which can lead to inefficient performance and a potential fire hazard. A clogged flame sensor can also cause your heater to cycle far too frequently between “on” and “off” modes. 

If you notice that the furnace flame has become yellow, it is essential to inspect and clean your furnace as soon as possible. Not addressing it immediately may cause your heater to produce a carbon monoxide leak.


Furnace cleaning should be done regularly to ensure the unit continues operating efficiently and safely. Warning signs such as what we have outlined in this article are indicators that it is time to get your furnace inspected and cleaned by a professional. Take your time; have your furnace serviced as soon as possible to maintain optimal performance.

If you need furnace maintenance in Pickering, Climate Experts is here for you! Our technicians have expertise in all makes and models of furnaces and can perform repairs, tune-ups, safety inspections, and more. Contact us now!

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