I used to see replacing furnace and AC filters as a hassle.
Now that I’ve seen the benefits of good filters, replacing them regularly no longer annoys me.
The right filter makes a big difference in the air quality of your home.
I started buying better quality filters that catch finer particles.
Since then, I’ve noticed less dust accumulating in my home.
Filtering an HVAC system is a simple concept, but there are some brands and filter media which should be avoided.
I’ll lay out just what to look for in a filter, and how to spend your money wisely.
Quick Pick: Nordic Pure is a better value, especially as a 6-pack.
Before you begin hunting for a filter, figure out your filter size.
You can find the size by taking a look at the side of your current filter.
You should see a number printed on the side; for example, 16x25x1.
Those three numbers are the height, width, and depth of your filter, measured in inches.
You don’t want any air gaps around the filter, so it’s important you purchase the right size.
MERV vs MPR Ratings
Filter ratings tell you how small of particles will be filtered from the air.
There is more than one different rating system in use.
MERV (Minimum Efficiency Value Rating) is most commonly used. Nordic Pure uses MERV ratings.
MPR (Microparticle Performance Rating) is 3M’s own rating system for Filtrete filters.
With any filter rating system, a higher number rating means smaller particles will be trapped by the filter.
So shouldn’t you just go with the highest rating?
Well, first off, a higher rating means more expensive filters.
Additionally, if you go with too high of a rating, it can put stress on your heating or air conditioning system. MERV 14+ or MPR 1900+ filters should only be used if you’ve made sure your system can handle it.
Here’s a guide to commonly used ratings:
- MERV 1-4 or MPR 100: Avoid these filters. They provide minimal filtering.
- MERV 5-8 or MPR 300/600: General use. Ok for those without allergies, pets, or young children.
- MERV 9-13 or MPR 1000/1200/1500/1900: Improved filtering for those with pets, allergies, or households with kids.
- MERV 14+ or MPR 2200/2500/2800: Generally only used in hospital, commercial, and industrial settings. A powerful HVAC system is needed.
To find exactly which Nordic Pure or Filtrete filter is best for your home, continue on to the comparisons below.
Side by Side Comparisons
These filters will catch fine dust particles and pollen, where MERV 6/7 or MPR 300 filters will not.
These two filters are well suited to homes without pets, small children, or allergy sufferers. They do a good job of reducing dust in the ducts and throughout the house.
Both Nordic Pure and Filtrete are pleated filters. They’re electrostatically charged to help attract particles.
Both brands use frames made of “beverage board” which is a type of cardboard that’s moisture resistant. They hold up well in high-humidity areas.
In terms of quality and performance, these two filters are effectively equal.
Pricing is where Nordic Pure comes out ahead. When purchased as a 6-pack, they’re about $10/pack less than the comparable 3M filters.
My Pick: Nordic Pure MERV 8
Stepping up to a MERV 12/MPR 1200 filter is a good idea when air quality is important.
Most pet dander, bacteria, allergens, and mold will be trapped by this level of filter.
So, if you have pets, kids, or people with allergies in your home, this is a great combo of air quality improvement and value.
These two filters are similar in performance. Filtrete has an edge at this level in the filtration of smoke and odor particles due to the carbon layer which gives the filter its black color.
Households with smokers, or those looking to reduce the spread of food odors, may notice a bit of improvement with the Filtrete MPR 1200.
Pricing is best on filters when purchased in a 6-pack, which is available for a lot of sizes for Nordic Pure MERV 12 filters.
Filtrete sells a few of the common sizes in 6-packs, but many MPR 1200 filters are only available as 2-packs or 4-packs. That increases the price per filter.
Expect to pay around 35% less if you go with the Nordic Pure filters.
Did you know that filters can help reduce the spread of viruses and bacteria?
This level of filter can trap very fine contaminants.
They’re of particular benefit in cold climates during the winter months. With the heater frequently running, the air is cycled and filtered more often. This can help prevent the spread of germs, which otherwise may thrive in the dry air.
If you have a newborn baby in the home, or if allergies really do a number on you, consider these filters.
Locations with smog or other air contaminants also benefit from filtration as fine as this.
The filter performance of the Nordic Pure MERV 13 and Filtrete MPR 1900 is nearly identical.
Nordic Pure offers some common sizes of MERV 13 filters in 6-packs. Filtrete MPR 1900 filters are mostly sold in 2-packs.
The Nordic Pure filters often work out to less than $13/filter in the 6-packs.
The Filtrete MPR 1900’s end up closer to the $20/filter range.
My Pick: Nordic Pure MERV 13
When Should Filters Be Replaced?
The general recommendation is to replace your filter every three months.
Really, though, it varies by how much your HVAC system runs and by the air quality in your home.
Here are the schedules I would go with.
Replace once per three months:
- 1-2 people in the home, no pets, average usage
- Two people, 1-2 pets, low AC & heat usage
Replace once per two months:
- Several people, no pets, average usage
- Two people, 3+ pets, low usage
- Several people + pets in the home, average usage
- Two people with 3+ pets, heavy usage
Here are some other reasons you may want to replace filters every 1-2 months rather than waiting 3 months:
- You have a baby or young kids in the house
- Your pets shed heavily
- Your home gets dusty quickly
- Respiratory problems impact someone in the home
One last point: if your filter ever is visibly dirty, it should be replaced right away. If it looks gray next to a new, white filter it needs to go.
3M’s Filtrete filters are the industry standard, and will not disappoint.
On the other hand, the 3M household name comes at a higher cost.
Nordic Pure filters are cheaper across the full range of filtration levels. They perform very well, and chances are you won’t notice the difference between brands – so long as you choose the right level of filtration.
If Nordic Pure’s lower pricing allows you to replace your filters more frequently, I recommend going with them.
Whichever you choose, I would go with at least a MERV 8/MPR 600 rated filter. It really does make a difference in the air quality and amount of dust.
If you want to further improve air quality inside your home, look into air purifiers.