If you are wondering what type of air filter to use in your air conditioner/heater, you probably have already discovered there is a large variety of air filters out there to choose from.
There are several factors to consider when the choosing the best air filter to suit your needs.
: level of difficulty ; interval of service
: level of desired filtration and its affect on system performance
3. Annual Cost
: Material and laborMaintenance
is something that can be overlooked at first. Afterall, it's just a filter, right? Filter types range from disposable to permanent. Disposables are pulled out, thrown away, and replaced with a new disposable filter. Permanent air filters must be removed, cleaned, allowed time to dry, and re-installed. Permanent air filters may or may not require electricity. Efficiency
is determined by a MERV rating of 1 thru 16 with "1" being the lowest and "16" being the highest. Low end residential air filters generally have a rating between 1 & 5. Medium grades range between 5 & 9. Higher grades are in the 9-11 range. Utimate is 11 - 13. The lower the rating, the lower the efficiency of air filtration but higher airflow due to lower resistance. The higher the rating, the higher the efficiency of air filtration but lower airflow due to higher resistance. Lower MERV ratings have minimal affects on your air conditioner/furnace performance. Higher MERV ratings can decrease the amount of air passing through the system creating system performance issues which could lead to system failure and/or decreased life. If Maximum efficiency is desired, it is recommended you consult with your HVAC contractor who can help you identify a filtration system to satisfy your needs without comprimising the performance and life expectancy of your heating and air conditioning system. Maximum efficiency air filtration will not only be capable of capturing fine particles, but it can also capture bacteria and smoke. If you determine that Maximum efficiency is not in your budget and/or not required, you should be able to install an air filter with a MERV rating of 1 - 11 without needing to consult with a contractor. MERV 8 has been laboratory tested to capture mold spores which are a big contributor to Mold in an A/C system. Additional Information on MERV Ratings - Click Here.
Lower efficiency filters allow more particles to pass through which could end up getting trapped in today's higher efficiency evaporator coils. Today's coils have much smaller gaps than their predecessors making them more susceptible to collecting debris and requiring costly professional cleanings. Annual Cost
is another often-overlooked consideration when deciding what type of air filter to use. To determine annual cost, you must try to determine approximately how often you will need to replace/service your air filter and the costs of labor & materials involved. I include labor because if you have a hard-to-reach air filter or a high efficiency air filter/cleaner that requires special care, you may need a contractor to perform the service for you. Of course, if you are doing the service yourself, there is no labor involved with the exception of your own time and gas, etc. If you choose the ever-popular disposable air filter route, you should consider pleated-type air filters. Pleated Air Filters
have more face area than standard air filters; therefore, they typically have a longer life expectancy - up to 3 times longer for every inch of filter thickness. In short, when determinining annual cost, you must calculate labor/material cost and multiply that cost by the number of times a year the service will need to be provided.
Proper maintenance and upkeep of your air filtration system is the single, most important service your heating & air conditioning system requires to keep it running at top performance and maintain peak life expectancy. Careful consideration is needed to determine what type of filter will meet your family's needs both on a comfort level as well as financially.