The 4-inch thick air filter has a clear advantage over the 1-inch filter when it comes to longevity, airflow, and maximum filtration potential. So, if it fits your oven, then a 4-inch air cleaner is better than a 1-inch air cleaner for improving air quality. A 4-inch filter will last longer and provide better air quality for your home. First, 4-inch filters cover a higher range of MERV ratings, with a slight overlap with 1-inch filters.
With a filter of 4, you'll get at least an 8 MERV rating. With higher ratings of up to 16, you can control supermicro contaminants such as bacteria, viruses and dust particles. Virtually any HVAC professional will tell you that thicker filters perform better than common 1-inch oven filters. Thicker filters, known as media filters, are generally 4 to 5 inches thick compared to ubiquitous 1 inch filters that you can even buy at grocery stores.
4-inch filters will change less than 1-inch filters. And the first thing I always checked was the oven filter, because a clogged one inch filter gets dirty very easily. For comparison, a 4-inch thick filter will have approximately twice as many surface areas as a 2-inch thick filter. These 4-inch media filters can have 20-30 feet of surface area with their pleated (accordion) filter material.
For example, because you will change 1-inch high MERV filters more often than 4-inch filters (see maintenance section above), you could save money with a 4-inch filter depending on the MERV you get. It is a known fact that the standard dimensions of the oven filter (length and width) have nothing to do with its efficiency. Most HVAC technicians recommend changing 1-inch air filters every 30 days, while 4-inch filters can be changed every 3-6 months. When comparing a 1-inch to a 4-inch filter, you will find that using a coarser filter has several advantages. Thicker oven filters, known as media filters, almost always perform better than cheaper one-inch filters.
Particularly vulnerable parts include the air controller or oven blower motor that works overtime to push and draw air through the dirty filter and the heat pump or air conditioning compressor responsible for circulating refrigerant between the outdoor and indoor units. With more surface area to trap contaminants in the air, a 4-media air filter offers a longer lifespan than a 1-medium air filter. However, with most HVAC systems, you should be able to adapt a media filter cabinet, either under the oven or on the side.
