How to Choose the Right Filter for Your Furnace

Furnace in the basement of a Minneapolis home.Replacing a filter is one of the most important steps for furnace maintenance in Minneapolis. Indoor air quality is important to the health of people living in the household, especially for individuals with allergies, asthma, and other conditions. The filter catches dirt particles and other allergens to help purify the air circulating throughout the home. When something is wrong with the furnace, the filter is one of the first places that we check. It needs to be replaced on a regular basis to ensure that the system will work properly. When we need to replace the filter, we check the following 4 factors to choose the right one for the furnace:


If the homeowners used the right filter for the furnace before, we can check the filter size by looking on the side of the current filter. If it isn’t written on the side of the filter, we can measure the one that’s there. The measurements should be taken in inches. Some typical measurements for filters include 16x18x1 or 18x20x1.

MERV Rating

The Minimum Efficiency Reporting Value (MERV) rating tells you how resistant the filter is to airborne contaminants, such as dust particles. The higher the number, the better the filter will be at cleaning the air that you breathe. We can check the MERV rating that the current filter has or discuss the needs of our customers in order to find the right one.


Hand holding new furnace filter next to furnace in Minneapolis home.The material chosen for the filter can impact the MERV rating. Fiberglass is the most common option that people use. It’s cheap, but it needs to be replaced often. It’s also the most ineffective at trapping airborne contaminants. Pleated filters are made from polyester or cotton. These types can trap contaminants, but they can also add too much resistance to airflow at times. Electrostatic filters are made of electrostatic cotton or paper fabrics. They are the best at trapping the small particles, but they can be more expensive. The one that should be selected depends on the needs of the customers and the budget that they would like to spend.


Many filters need to be replaced on a regular basis. We advised our customers to do this every 2-3 months. They should do it more often if they live near construction, experience high winds, or have a member of their household with allergies or other conditions. It can be helpful to buy several filters at a time in order to be prepared to replace them. On the other hand, if they don’t want to replace it, they can also purchase permanent filters. These ones can be washed and replaced. They tend to be more expensive, but they won’t need to be purchased every couple months anymore.

In order to stay on top of furnace maintenance in Minneapolis, the filter should be replaced on a regular basis. We can help our customers determine which one they should choose for their furnace. In the end, it comes down to the budget and needs of our customers, as well as the size of their furnace. Based on these factors, we can determine the right one to purchase to keep the system working properly for them.