Every great hero has an equally great and often overlooked weakness: Superman has kryptonite, Achilles a bum heel, and Batman famously cannot let go of the past. Now imagine you had your own hero in your home. A mighty hero that kept your family from freezing, your pipes from bursting, and your furry family members from cowering in the cold of winter. Now imagine this hero that does so much to keep your fortress of solitude from becoming a den of ineptitude had a weakness. The hero, neutralized by its kryptonite cannot stop old man winter from unleashing his freeze ray (does old man winter have a freeze ray?) upon you, your home, and your family. Terrifying I know. However, much like these great heroes you can play the part of the side kick and ensure their safety and success. The hero: your furnace. Its weakness: A dirty filter. That’s right the insignificant little piece of paper and cotton that you forget about most months of the year could be the downfall of the one thing that keeps you from the bitter cold. This small seemingly insignificant, easily forgettable piece of material is the one thing that protects several key components of your furnace.
The blower motor on your furnace is the engine in the machine. It is what moves all that sweet sweet hot air throughout your home. Without the blower motor there is no heat, period. Many newer furnaces feature safety switches that will disable the flow of natural gas to the furnace if the blower motor does not come on. So, what does your furnace filter have to do with the blower motor? Simply put, dust. Like any electrical system dust wreaks havoc on your blower motor. Without frequent filter changes dust can build up on the blower motor causing it to over heat and burn out. At best this will reduce its ability to reach full air flow capacity, at worst the motor will completely burn out and cease to work. In extreme circumstances when the filter is completely clogged they can become like a cloth balloon expanding and eventually under the pressure of the motor get sucked into the fan itself. When this happens, they can cause the motor to seize and be rendered useless. Depending on the kind of motor that your furnace has repairs can cost anywhere from $150 all the way up to over $1,000 in emergency situations.
If blower motor problems sound ominous and expensive then the next key component that the filter can affect will be downright terrifying. Your furnace mother board is the brains of the whole operation. Everything in your furnace is controlled by this small piece of silicone and wire. Much like the blower motor if the mother board gets covered in dust it can over heat and short out. Without the furnace mother board nothing will work in your furnace. Safety switches will not be able to tell the furnace it is ok to fire, motors will not be allowed to turn on, and above all else there will be no heat. Mother boards come with possibly hefty price tags as well, pricing depends on brand and the age of the furnace, but you can expect to pay $400 and up to get one replaced.
All of this does not sound pleasant, and its not. Anyone who has had to deal with a home without heat in the middle of winter can attest to that, and anyone who has had to try and get service done on their furnace after hours can tell you how much money it cost to get a technician to your door. So, lets wrap up the bad news, depending on the brand of your furnace, dust can get on some of the key safety switches inside your unit and disable them as well. Flame rod sensors, high temperature limits, and other key parts can keep your furnace from working properly. Now these parts are cheap in comparison to the other parts that we have already discussed but it can be costly and time consuming to diagnose and find exactly which one has been disabled.
Now for the good news, while individually all these parts may fail on their own a lot of trouble can be avoided simply by ensuring your furnace filter is changed regularly. The best recommendation is to change your furnace filter at least once per month. Now you may think that using expensive filters will extend this time and protect your furnace but his is not true. Expensive filter often make use of more tightly knit media which can build up dust and clog faster. The best kind of filter to use is a cheap filter that allows air to move freely. It is a fine balancing act between allowing air to move and keeping dust out of your furnace. A cheap disposable filter changed often is usually the best solution to the issue. If you have people in your home who require a high level of filtration to help with their health it is a better idea to invest money in a different form of air quality such as an electronic air cleaner or a UV filter. So be a good side kick, put on your cape and help your super powered friend protect your home and your family, keep its weakness from becoming its downfall. Go now, change the filter. Firefly over and out.