There is always a nice reason for everything, but i suppose everyone should know that by know; Heating, Ventilation plus A/C professionals would not just tell you that your Heating, Ventilation plus A/C system air filter needed to be changed for no reason, then air filters can become really so clogged. In fact they collect so much dust as well as dirt in the matter of only a month, some people have so much dirt as well as dust collect that they need to change the air filter every month. Some people only change it every six months. However, you need to know your home as well as where you live. If you do not change the air filter often, there are some things that could happen to your home, however the air quality in your home goes down. The dirt as well as dust could beginning to travel through as it gets pushed right through the filter by the strong air being pushed through. The Heating, Ventilation plus A/C system could stop working altogether. If the Heating, Ventilation plus A/C air filter does not work, the system could have an automatic shut off in which it will not operate, only some systems are able to do this though. If you do not have an automatic shut off, then you could potentially beginning a fire within your system. The dirt as well as dust could become so moderate from trying to push through the moderate air in the filter that it starts on fire. So, in no way is having a clogged air filter a nice idea, however make sure to change your air filter on a common basis. I promise that they are not lying to you. It is all for something.