The short answer is, no, they’re not all the same. In fact, there are many different types of air filters available and choosing the right one can make a real difference in the lifespan of your HVAC system.
It is a general recommendation that you should change your air filter in your home every 30 days when using less expensive fiberglass filters. High-end pleated filters can last as long as 6 months, but these typical guidelines assume average use and don't take into account the size and type of filter.
To understand the differences in the filters available, there’s a couple of things you need to know.
1. All filters are rated using the MERV scale. Filters for residential use are generally rated from 1-13, with higher-rated filters being used in places like hospitals and laboratories.
2. Higher-rated filters have smaller openings, which is supposed to make them able to catch smaller particles in the air. A MERV 2 filter will only catch the largest particles, while a MERV 10 filter is supposed to catch very small particles like pet dander.
3. You might think you should just get the highest MERV rating you can find for a price you can afford. But it’s not quite that simple. You see, the higher the MERV rating, the more the filter restricts air flow.
4. If the air flow is restricted by the filter, then the HVAC unit has to work harder to pull air through it. This means that a higher MERV filter can cause the unit to burn out or the coils to freeze. Uh oh.
5. The truth is that the higher-MERV residential filters don’t really do that great of a job cleaning the air. Plus, they get clogged up with dirt and dust very quickly, which reduces the air flow to your HVAC unit even more.
For our customers, we recommend using the cheapest, lowest-MERV disposable filters, combined with the above. These filters will protect your HVAC unit from the dust and dirt that could actually harm it, while allowing the air to flow freely. That way your unit won’t work too hard and shorten its lifespan.
Plus, these filters only cost about $2 each, making it easy to replace them every month. Regularly replacing your air filter is the best thing you can do to help keep your HVAC system humming along. A clean, basic filter beats a fancy, dirty filter every time!