Your home furnace filter is probably the most approachable part of the heating and air conditioner system. You know your suppose to replace it, but like most other chores it either gets neglected and sometimes simply forgotten.
Now I can’t reach through the computer and change it for you but I can save you some time and money when shopping for a replacement furnace filter. Hopefully that minimizes the task of changing it a bit.
For starters I must clarify that this is for 1″ thick filters only. This does not apply to specialty filters such as space-guards, electrostatic or air cleaners.
There is a fancy rating system for filters known as MERV. All you need to know is that the higher the MERV rating the finer the particle it will collect and vice-a-versa. The lower the MERV rating the larger the particle that passes through.
CHEAP FIBERGLASS FILTER– NO
Your furnace and air conditioner are designed to run properly with a certain amount of air flow. The manufactures want you to use the cheap fiberglass type. These filter have a very low MERV rating of 1-4. If you don’t mind some dust in your house, on your furniture or in the air that you breathe than go for it. But I find that most people want just the opposite. These fiberglass cause next to zero resistance for air flow, which your equipment loves, but you are left with dust everywhere which you hate. The only time I recommend this type is if you are absolutely horrible at remembering to change the filter. They are very forgiving. You can go a long time without replacing them. Just be wary of what grows there…
EXPENSIVE 3M, ALLERGEN TYPE FILTER- NO
The old adage of “you get what you pay for” is NOT TRUE here. This type of home furnace filter has a high MERV rating from 9-16! These can cost up to $20 per filter and sometimes more. While they do filter the smallest of particles in your air they restrict the air flow well beyond what the furnace and AC require to work properly. The WORST part is that they need to be replaced MORE often. At least once per month. If you fail to replace them often enough you can and will damage your system. That means you spend roughly $240 per year or you pay hundreds of $$$ to pay for REPAIRS.
INEXPENSIVE, PLEATED FILTER- YES!!!
I always tell my customers this; “Buy the CHEAPEST, PLEATED furnace filter you can find. DO NOT spend more than $3 or $4.” It is a happy compromise for humans and equipment alike. The MERV is 5-8 which will remove most dust while allowing the furnace and air conditioner to breathe. Replace them every 3 to 4 months depending on your homes lifestyle (kids, pets, smoking). A great balance for your home and you will only need to spend about $12 per year. That is less than the cost of 1 expensive filter for the entire year.
I hope this removes some of the guess work when you replace you home furnace filter. Again remember, “Buy the CHEAPEST, PLEATED furnace filter you can find and DO NOT spend more than $3 or $4.”
Breathe Easy and Stay Comfortable