It really depends on the home and personal preferences, but as a general rule, 20x25x5 air filters are stronger than most air filters, so most homeowners only use two to three of them per year. The general recommendation is that oven filters should be replaced at least once every 90 days. However, there are many other factors to consider when deciding how often an oven filter should be changed, such as the size of the filter and the type of fan motor in your air conditioning system. HVAC systems may not have heating components and therefore do not need an oven filter.
On the other hand, if you use your air conditioning system almost constantly, you'll have to change the filter every few weeks (especially if you use fiberglass filters). During the winter, when the oven is used more often, you will have to replace the oven filter more often. During a remodeling project, replace the furnace filter every 30 days, or even more frequently, to prevent construction-related dust from circulating around the house. The primary purpose of an oven filter is not to clean the air you breathe, but to clean the air that passes through the oven and other HVAC equipment.
Be careful not to confuse Honeywell oven filters with your HEPA air filters for purifiers, which last much longer. A Honeywell oven filter will have the same filter replacement recommendations as standard filters. We also offer filters for 5-inch ovens (16x25x5 or 20x25x), brands of air filters for the whole house and filters for rigid cell ovens.