Why is your furnace filter black? What size furnace filter do you need when it comes time to change the filter? Many homeowners have questions about their furnace air filters and aren’t sure where to look to find that information.

First and foremost, a dirty furnace filter overworks your HVAC unit and hampers its ability to be energy efficient. For that reason, you should replace your furnace filter regularly.

How do you choose the filter that’s right for your furnace?, Understanding that there are different types and sizes of furnace filters is the first step in finding the right one. Plus, having knowledge of a filter’s MERV (Minimum Efficiency Reporting Value), will help a homeowner understand how effective that filter is.

Understanding MERV Ratings

To understand the efficiency and effectiveness of a filter, one must first understand MERV ratings. MERV, which stands for Minimum Efficiency Reporting Value, rates air filter effectiveness. A higher value MERV means that the air filter has a finer filtration, meaning less dust particles and airborne contaminants can pass through. The MERV scale ranges from one to twenty, with twenty having the finest filtration.

Types of Furnace Filters

Furnace filters come in many different types. Here are a few options for you to choose from:

Disposable Fiberglass Filter

This is the cheapest type of furnace filter. It's made of 1-inch spun fiberglass. It screens out large particles such as dust, debris, textile fibers, sanding dust and lint that could clog your HVAC system. It often has a MERV rating of 2 to 3. This filter is good for you if you're a renter and don't have asthma or allergies. This type filter typically costs between $1-$2 and can be found at a local hardware store.

Disposable Pleated Filter

This popular filter is made from cotton paper or polyester. It removes smaller particles like mites and spores. It's relatively inexpensive and has a MERV rating of 6. You need to replace it frequently to prevent clogging and restriction of airflow that makes your furnace less efficient. This filter can be used in commercial buildings, residences or industrial workplaces.

High-Efficiency Pleated Filters

These are usually made from synthetic polyester or pleated filter paper and are four to five inches thick. They can screen out very small particles. The filter is attached to a metal grid to prevent links or fluttering. Their MERV rating ranges from 14 to 16. They are beneficial to people with autoimmune disorders or respiratory problems. They are expensive to run, costing around $100 and can only be used in special housing because of their thick size.

How do I Install a Furnace Filter?

Once choosing a filter, it comes time to install it. Installing your filter can be done in three easy steps.

If you are unsure where the filter box is, look at the ductwork. The heating duct is located near or at the top of the furnace, and the cold air return is located near the bottom, which is where the filter box will likely be located.

There’s a chance that your filter box will have a door, or possibly that the filter will be visible inside a notch that the filter slides into. From here, remove the old filter and discard. Your new filter will have air flow arrows along the sides. The arrows indicate the correct orientation of of the filter. A fun little tip to remember which way to put your filter in is that the arrows always point towards the furnace!

With the arrows pointing towards the furnace, slide the furnace filter in the air box. And you’re done!

Quick Furnace Filter Tips

Furnace filters need to be replaced every month, or when you can no longer see them in the filter box. If you’re unsure of the size of filter you need, correct filter measurements for your furnace will be located on the filter box.

Always turn the furnace off before replacing the filter! Not turning the furnace off could result in injuries such as burns.

Let McCoy’s Help you

Buying the right furnace filter will save you money and improve your home's air quality. For more information on selecting a furnace filter, contact us at McCoy’s Heating & Air. We aim to provide our customers with most accurate information and the highest quality service.

Have you ever had a unit installed, serviced or repaired from McCoy’s Heating & Air and want to share your experience with the Jackson community. Please leave us a review! We want to ensure that we are providing our customers with the best service possible.