Maintenance, Resources + Tips

Furnace Filter Basics

Your furnace filter is an important part of your home’s heating system. Its main purpose is to remove particles and debris from the air entering your furnace in order to protect the mechanical components of your furnace, such as the motor.

Here are some basic tips to make sure that your filter is doing its job:

  1. Check & change your filter regularly – This is typically every 3 months, but more often if conditions require (ex. if you live in an area with a lot of dust, if you have pets who shed, or if you run your furnace fan continuously.
  2. Never try to clean a disposable filter – the materials break down over time and are not meant to be reused or cleaned. Looking for a permanent filter? Find out more about our exclusive Air Renew Electrostatic washable filters.
  3. If your filter doesn’t fit, it doesn’t filter – Air takes the path of least resistance so it is important that your filter fits in as closely as possible. It needs to reach right to the end of the filter track, and there should not be a visible gap on either the plenum or the furnace side. If your furnace needs a specialty size, you should get one, or, get your filter slot changed to fit a standard size. If there is a gap to the sides of the filter and there is not a snug fitting door, using a piece of duct tape down the slot to seal the gaps is a good idea.
  4. More “Merv” is not always better – A good Merv rating for residential use to balance particle trapping with air flow is between 5 and 8. You should consult with an HVAC professional before using a very high Merv filter, as your system may not be able to handle the air drop (decrease in airflow) caused by a very high efficiency filter. If you have a 2” or a 4” filter slot, using a filter with a higher Merv rating will be less of a concern, as the higher surface area of a thicker filter causes less resistance to air.
  5. Consider Running Your Furnace Fan Continuously – To encourage continuous air flow and filtration, run your fan continuously. Keep in mind that if you have not done this before, you will need to check your furnace filter more regularly, as running the fan will pull more air through the filter and cause it to become full quicker.

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Alberta Furnace Cleaning Reviews

I had my ducts and vents cleaned in March 2021 and I was impressed by how thoughtful Richie was. As he cleaned the ducts, he made sure to not leave a mess when he went from room to room. When it came to the dryer duct, Richie even cleaned up the giant dust bunny that he pulled out, and this was outside! I would definitely be back for my next duct and vent cleaning with Alberta Furnace Cleaning! Thank you to both Xianglong and Richie!

- Sophia Mah

Equipment was new and well maintained. Staff were pleasant to deal with and explained what they were doing. They efficiently dealt with their business. Cleaned up after themselves. No concerns at all.

- Barry Maron

They came early and did an amazing job cleaning all of our vents, making our dryer vent clean as a whistle and making our home safe and clean again! I had my 10 month old at home at time and they were so kind about making sure he was okay with the noise. Cannot thank them enough for their work! Get your services done by them everytime!

- Karen Sarsiat

Called around 11am and they were able to come out same day! Very prompt, friendly and got the job done quickly. They were upfront and clear about their prices. Would definitely use their services again.

- Patricia Smith