Most of the companies and experts that the furnace filters should be changed or at least inspected once a month during the heating season for optimal healthy environment and furnace performance. But many homeowners find this answer less satisfying and indeed there are more aspects related to this area than one can imagine. That makes it more complex but the process is equally rewarding once you understand all the aspects related to the changing of furnace filters.
The frequency of changing the furnace filter varies from house to house and filter to filter. Some of the filters need replacements frequently while some of the conventional models do not require changing this often and can last long. The other side to conventional filters is that they are not exceptionally well in blocking dust particles so the blocking of the filter means that it will work well and will start blocking minute dust and other allergens. Changing furnace filter also depends on the situation. This means, if you have more pets or anyone in the house smokes regularly inside, then the filters will have to be changed more frequently, say once every month. Based on all of this, the recommendation is simple enough: Buy a enhanced filter, look at it monthly and plan to change it every three months, or every season if you have a arrangement heating and air-conditioning system that runs year-round.