Perhaps before answering the question of how often you should change your furnace filter, maybe it would make more sense to understand why it is important to change your air filter and why it is not something that only needs doing ‘when you feel like getting round to it.’

There are three critical reasons why you should regularly change your HVAC filter or furnace filter.

First, there is the question of efficiency. If your furnace or HVAC unit can’t draw in fresh air with ease, you are putting undue pressure on the operating system, which will only ever result in one thing – frequent breaking down of your unit and a (drastically) shortened lifespan.

Second, there is operating efficiency. Furnaces and HVAC units are relatively finely tuned and, a bit like a car engine, if not looked after, it will start to guzzle fuel. When you think of how much energy your HVAC unit or furnace consumes over the period of a year, also think of what it would mean to have that bill either increased or decreased by 10%. Maybe now you will understand why regular servicing is such good value.

Third, there is the question of smell. Filters are there to trap dust, hair, and all sorts of other airborne particles. If you allow these to build up over a long period of time, eventually your HVAC unit or furnace will be drawing in air that is sucked through all that debris, heated in the heat exchanger (and we all know that when you warm something up the smell, whether pleasant or not, is enhanced), and then pushed out through the vents in your home. Nothing makes a home smell like it is in need of a thorough cleaning, from top to bottom, than a clogged-up HVAC or furnace filter, no matter how spotlessly clean the home may actually be.

So, bearing the above in mind, perhaps you will understand why it is advisable to change your furnace or HVAC filter regularly, without fail. As to how often that should be, well that can depend on a number of factors. If you live in a modest-size property, on your own, and have no pets, then you are not going to have to change your filter as often as someone who lives in in a large family house with four children, two dogs, and two cats, as they are going to generate far more dust and hairs, the usual culprits to be found in an HVAC or furnace filter.

Finally, the frequency of filter change will also be dictated by the size of filter needed. As a rule of thumb, you should change your furnace filter every three months for 1-2-inch filters, every six months for 4-inch filters and once a year for 5-inch furnace filters.

If you’re still not confident and want further advice, just give us a call and we’ll be glad to give you some helpful tips and advice regarding your HVAC or furnace filter.