What’s a filter for? Not what you think…

What's a filter for? Not what you think…


As the warm spring weather arrives, homeowners frequently ask me if there is anything they can do to ready their cooling system for summer. There are a few simple steps that one can take to assure their system will be ready to take on the hot muggy days of summer. Over the next few months I will go in depth about some helpful cooling tips I have discovered over the years.

This month I would like to give you some insight on the first and most important step in summer cooling preparation-making sure to properly change the furnace air filter. This should be done every month during the months when either the central heat and air is operating. At under $3.00 a piece, it’s the best investment you can make in your home’s heating and air condition system, considering the fact that over 75% of the service calls we receive in the first thirty days of the cooling system involve a dirty or improperly-sized filter. Over three-quarters of the time, our technicians are cleaning dirty cooling coils, blower wheels and clogged condensate water drains caused by homeowners not changing their air filters.

Most of our customers incorrectly believe that the job of their furnace filter is to remove airborne dust, dirt and pollens from the air their family breathes. An even larger segment of our customers also incorrectly believe that the job of their furnace filter is remove pet dander, bird feathers, fish tank smell, cat pan stinks, small toys that junior threw down the floor grills and smoke from uncle Harry’s cigar at Christmas. Well, they are all wrong! The job of a properly designed and installed furnace air filter is to keep the cooling coil/radiator clean and efficient during the life of your system. Inside the duct work above your furnace is a cooling coil/radiator called the evaporator coil, and outside of your home is a device called the compressor/condenser. The job of the coil/radiator is to remove the moisture and the heat from the air in your home and just like the coil/radiator in your car, your home’s cooling coil needs just the right amount of airflow going through its tightly packed fins. Just as your car will overheat if your fan belt breaks, your air conditioner will overheat and stop working if coil becomes clogged with dirt.

The fan blades that provide this airflow are in your furnace and they are also protected and kept clean by a regular furnace filter changing. If your furnace blower or your cooling coil becomes clogged with dirt, a professional repairperson with must be called as this cleaning requires removal of both components and is very costly.

A dirty coil/blower wheel will cause reduced airflow and possible icing of the compressor/condenser and cooling coil. This icing causes many problems including the complete destruction of your compressor/condenser. A unit with a dirty coil or furnace blower will run longer generating higher power bills and will not be as efficient in transferring heat as a clean coil and blower.

It is very important to use the correct size filter so that all the incoming air is directed through the surface area of the filter. Do not bend or fold a too large filter and make sure your filter is properly held in place by a wire retainer or clip. Remember there is up to 2000 cubic feet of air blowing through your filter and it will be pulled out of place unless firmly held in by a filter retainer clip. I can’t tell you the number of times I find a furnace filter all mangled up and torn by the blower and dirt just blowing right on the coil. It’s very hard to get the filter springs back in place after you change the filter. Try lying down on the floor and with a flashlight in hand partially crawl in the blower area to observe the filter spring clip holder. Keep at it until it latches in place. If you are lucky enough to have an external filter rack or holder, be sure and reinstall the door correctly to make sure no air leakage occurs.

If you are using those 99-cent blue fiberglass throwaway filters, STOP RIGHT NOW. Those filters are designed to stop dirt particles the size of junior’s toys he throws down the grills and they do a darn good job of it! But everything else smaller flies right through them and builds up on the surface of your cooling coil where it joins with condensate water to form a product “coil scrounge”. Invest in the MERV 8 1″ pleated filters that cost about $3.00 a piece at your local home improvement store. Make sure you buy a dozen at a time to make it easy to do. You will never remember to go to the store every month. If you have an air cleaner or a hard to find filter size do not give up. Give me a call and I will give you the name of a wholesale supply house in your area that WILL sell to you. I have spoken to the manager and they will be glad to help you directly. In the past I have heard from homeowners that supply houses will not talk to them unless they are “in the air conditioning business”. I will gladly give you the name and number of this one supplier you can purchase a full array of air cleaner and media filters at a very reasonable price.

By changing your furnace filter often and correctly, you can rest assured that you have done one of the most important functions in assuring continued comfort, efficiency and life span of your home’s central heat and air system.

Call or text Reliable Heating & Air today for all your heating and air conditioning service needs at (770)594-9969 or visit us on the web at www.reliableair.com

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