Why Furnace Filter Replacement is Important and How it Affects Your Air Conditioner Performance

One of the easiest and cheapest things a home owner can do to mitigate costly service calls is to replace the furnace filter on a regular basis. This is true for air conditioning and heating seasons. The frequency of replacing your furnace filter will depend on several factors that we will talk about in a minute, first lets look at what a filter really does. Filters are rated by how well they block air born particulates, the higher the efficiency rating the smaller the particulate the block from traveling through your supply duct work into your home. As the filter becomes loaded with dirt, the efficiency gets better and better. This sounds like a good thing but as the dirty filter gets more efficient at stopping particulates, it also gets less efficient at letting air move through it. This causes less air flow past the air conditioning coil or heat exchanger. When this happens, your home may not get cool in the summer while your air conditioner outside runs and runs. Another problem dirty filters cause is that if they get so clogged they collapse, they allow dirt directly into the fan, then to the entering side of the air conditioning coil in the furnace. This could, over time, cause your air conditioning coil to become clogged with dirt and again not pass the required amount of air through it to cool your home.

The first and probably most influential factor to filters getting dirty is the condition of the inside of the return air duck work. Due to the nature of the return air side of a fan, the return air duct will become dirty over time. Depending on the particular building codes of the area you live in, the return duct work might only be the metal duct that emanates from your furnace. The rest of the system might use the space between the floor joists and wall studs. These areas of your home are great places for spiders to live and build webs. These webs become loaded with dust from your home and eventually find their way to your filter. Another factor is the area you live in itself. When you live in a new home subdivision or maybe in a agricultural area, there is a lot of air born dust. This dust gets into your system through the return system and clogs your filter. Large cities have different particulates that enter your home and therefore your duct system. The different types and sources of particulates are too numerous to list them all in this one article.

So, how often should you change your filter? The answer is different for different areas and filter types. The higher efficiency filter you use, the more often you will need to be replace the filter. The more you use your air conditioner or furnace, the more you will need to replace the filter. The best way to know how often your furnace filter needs to be changed is to physically look at the filter for several months during the heating and air conditioning seasons to see how fast your individual situation dictates. Once you determine an appropriate time interval for filter replacement, there are thermostats that can be programmed to help to remind you when to change your furnace filter.

The furnace filter is a key part of the efficiency of your air conditioning and heating system. Without the furnace fan being able to move the required amount of air over the air conditioning coil and thus through your air distribution system, your air conditioner can not cool your home efficiently and this costs you money.