ThankYouJack wrote: ↑Sun Apr 05, 2015 8:30 am
How often do you replace them and where do you get them? I've heard that you're suppose to replace them every three months. My house has 4 of them, so if I pay $15 / each that would be $240 / year.
Depends on what kind of filter you use:
1) Cheap fiberglass/wool, lightly used - once per 6 months (this is me/us, who are out ~12-15 hrs per day)
2) Cheap fiberglass/wool, normal use - once per 3 months (this is my parents, who leave hvac running all the time)
3) 1" pleated, normal use - once per month (once these pick up a bunch of dust, I can hear them, and my HVAC fan screaming so I would change more often if you use these)
there are a bunch of high capacity models that all vary on capacity/time between changes and I don't have knowledge about them.
I generally agree that almost everyone with a 1" filter should be using cheap fiberglass since your HVAC was likely installed and designed to handle that. If you need additional air filtration for allergies, then I might buy a separate purifier as it will be more effective and have no adverse impact on your HVAC system.