Have you ever taken your old filter out to replace it and it doesn’t ‘look’ dirty?
“Why should I change the filter if it doesn’t even look dirty?!” …But my a/c guy told me to “change it every month”…what should I do?”
Here is ‘my’ simple answer:
“Did your comfort system run for any length of time in the last 30 days?” No? It was turned off all month long; the fan didn’t even come on. “OK, leave the filter in, there can’t be any dirt on it if the heat, cooling or fan never came on”.
“Yes, my system did operate in the last 30 days”
Change the filter. Remember, it doesn’t have to ‘look’ dirty to ‘be’ dirty.
Your comfort system’s air filter is usually an easily maintained item AND it is the number one culprit to air conditioning system failures; sad, but true.
The filter really only has one specific purpose: To keep the components of your heating/cooling equipment from getting dirty. I might add that it helps keep the ducting clean as well but again, that is not its primary function. It is there to keep the blower wheel and motor, the heat exchanger (for gas heat systems) and the cooling coils from getting dirty. Dirt build up on any of these components can destroy efficiency (increase utility consumption) and could cause catastrophic failures of the heating and/or cooling system.
If your system uses ‘throw-away’ (paper boxed-in type media; usually 1” thick) you typically have just two options at your local hardware store: Poly or Pleated. Pleated filters cost more and most of them will boast that they will “clean” the air better.
A Poly filter is around 5-15% efficient; most off-the-shelf Pleated filters; 30% efficient. So if you are using a filter that is 2 times more efficient at trapping particulates, should it be changed more often? In most cases they are still good for approx. a month. Pleated filters do have more surface area and can therefore ‘hold’ more particulate but it IS also more efficient, so it is holding MORE and therefore should be changed just as often.
Whenever anyone asks ME how often they should change their filters I will usually say “Never!” After the shock I will tell them that they could have a filtration system that is professionally installed right at the air intake of the comfort system, it could have an efficiency of 95+% and require ZERO time or effort form ME. The ultra-high efficiency media is replaced annually* by my air conditioning contractor when they come to do my spring/fall maintenance. I do NOTHING.
I’m glad you asked; call us at (210) 987-5587 for a free in-home evaluation of your filtration needs.
* In some cases media replacement is required bi-annually