All forced-air heating and cooling systems require an HVAC air filter. The filter prevents dust and debris from entering your furnace and air handler. Air is constantly drawn through the filter whenever your air conditioning or heating is running to prevent dust and debris from gumming up the blower fan or damaging your furnace. The filter also improves indoor air quality by trapping pollen, dust mites, mold spores and other common household allergens and pollutants. However, suppose the filter does not get replaced regularly. In that case, it can lead to numerous issues that can affect the efficiency of your cooling and heating and contribute to higher energy costs. Let's now take a closer look at how often the air filter needs replacing and how to choose the right filter for your system.
How To Know It’s Time To Replace Your Air Filter
To keep your HVAC system running smoothly, you need to replace your air filter once every three months at the very least. If you live in a dustier area or have an older home, you may want to replace the air filter as often as once a month. You will also want to replace the filter more frequently during the hottest and coldest parts of the year when your air conditioner or furnace runs throughout most of the day. The more your HVAC system runs, the faster the filter will get dirty and need to be replaced. It is always best to check the condition of your air filter at least every few weeks. If there is a thick layer of dust and hair on the filter, you can gently clean it off by hand to extend its life. However, if the filter looks dark gray or black, you must replace it. You can also check the filter's condition by holding it to the light. If you can't easily see through it, it's time to throw it away and replace it with a new filter.
Why Replacing Your Air Filter Is So Essential
As the filter gets dirtier, it eventually becomes so clogged that very little air can flow through it. This decrease in airflow will force the blower fan to work much harder to draw air through the filter and circulate it throughout the ductwork. Unfortunately, when the fan works harder, it can lead to the motor wearing out and needing replacing much sooner. The lack of airflow coming into the system will also drastically limit the effectiveness of your heating and cooling system. Very little hot or cold air will flow out of your vents if not enough air can get into the system. This lack of airflow means it will take your furnace or air conditioner far longer to heat or cool the house. As a result, your energy bills will be much higher, your comfort will suffer, and your HVAC units will likely need more frequent repairs and have a shorter lifespan. A clogged air filter also has the potential to cause significant damage to both your furnace and your air conditioning system. During the winter, a clogged filter can make it impossible for the furnace to disperse all the heat it creates appropriately. This can quickly cause the furnace to overheat and automatically shut down. Unfortunately, all that heat can also crack the heat exchanger inside the furnace. A cracked heat exchanger will cause the furnace to produce very little heat. Still, the more significant issue is that it can allow carbon monoxide to escape from the combustion chamber into the ductwork and circulate throughout the entire building. Cracked heat exchangers are one of the most significant sources of carbon monoxide and can lead to fatal CO poisoning. Dirty air filters are also one of the main reasons that air conditioning systems freeze up. When there isn't enough hot air flowing into the air handler, the AC refrigerant can stay cold enough that condensation will freeze on the evaporator coil. When this happens, the system won't produce any cold air until it can thaw out. If you attempt to run your AC when frozen, it can potentially burn out the compressor motor. Should this happen, you will typically need to replace your outdoor AC unit.
Choosing the Right Air Filter
When buying replacement air filters, please consider their size and efficiency. Choosing the right air filter is simple since only one size will fit your system. However, efficiency is slightly more complicated since it depends on how effective your plan is, how much you're willing to pay and your specific goals. Most air filters have ratings for efficiency using the MERV (minimum efficiency reporting value) scale. This scale goes from the least efficient MERV 1 up to MERV 16. Most filters designed for use in residential HVAC systems will range between MERV 5 and MERV 13 The scale technically goes to MERV 20, but anything above MERV 16 is considered a HEPA filter. HEPA filters are highly efficient and will filter out more than 99% of all airborne allergens, contaminants and pollutants. However, this filtration level is only necessary for surgical operating rooms and other highly sterile environments. Therefore, hospitals don't typically use HEPA filters except in a few areas. The more efficient the filter is, the more it restricts how much air can flow through it. As a result, HEPA and high MERV filters can only go with systems with extremely powerful air handlers. Unfortunately, residential systems aren't nearly powerful enough, so you should generally never use anything above MERV 12 or 13. If the filter is too efficient, it will have the same effect as when the filter is clogged. If you're mainly looking to prevent damage to your HVAC system, you are best to go with a MERV 5 or 6 filter, as these will always be the cheapest. However, if you are more concerned about indoor air quality, you may want to upgrade to anywhere from MERV 8 to 12. These higher-rated filters are an excellent choice for anyone with severe allergies, asthma and other respiratory problems, as they should filter out the vast majority of allergens. You also have the option to choose between disposable filters and washable filters. A washable filter will cost more upfront, but it is the cheaper option in the long run. With proper care, washable filters can last up to 10 years. Despite the slightly higher cost, most people still use disposable filters simply because they are much more convenient. If you do decide to go with a washable filter, you will need to thoroughly clean and wash it just as often as you would replace a disposable filter. If you're worried about the higher cost of disposable filters, you can usually save quite a bit if you buy them by the case instead of individually.
Your Trusted HVAC Experts
At McCrea Plumbing Heating Air, we offer a full range of HVAC services for residential and commercial customers in Payette and throughout the Treasure Valley. Our certified technicians install, repair and maintain furnaces, heat pumps, air conditioners and ductless mini-splits. We also offer duct cleaning, duct sealing, thermostat and indoor air quality services. We also have a team of plumbers specializing in water heaters, water quality, well pumps and all plumbing repairs and installations. Contact us today if you need any cooling, heating or plumbing service.