When it comes to buying furnace filters, there are a few factors to consider. The MERV standard is mainly used to measure the performance of filters designed for forced air conditioning systems. HEPA (High Efficiency Particulate Air) is a much stricter standard than MERV. Because HEPA filters have such tight filtration, they tend to restrict airflow so much that they are impractical for most residential forced air systems.
HEPA filters, on the other hand, are often used in air purifiers and vacuums. More expensive electrostatic oven filters capture smaller particles and need fewer changes than cheaper (pleated) and cheaper (woven fiberglass) filters. If you have allergies, consider using electrostatic filters. As ovens vary, so do their filters.
Not every filter is ideal for every oven, or even for every home. However, there are a handful of filters that we found to be the pillars of the industry. The thickness of the air filter ranges from 1 to 5 inches deep; some options are more common than others and the oven can determine the thickness you can use. To be sure, you should check if your oven manufacturer has a maximum MERV rating that your oven model can use. Disposable fiberglass oven filters are usually the cheapest and lowest quality available. When it comes to thickness, the 2-inch oven filter is the winner.
However, these two are not drastically different in thickness. Air filters generally come in a variety of standard sizes, and some can be adapted to fit different sized filter boxes or air return openings. If the air filter compartment in your oven is only 3 mm thick, then a 1-inch oven filter is the better choice compared to the 4-inch filter; however, a 3-inch thick air filter is the better option. You should also be aware that an incorrect oven filter or poorly maintained filtration system could result in poor furnace efficiency or even furnace failure. Regardless of your experience with ovens and how they work, choosing which type of filter to use can be time-consuming.
There are also visual cues you can look for when deciding whether to replace your oven filter. So, if it fits your oven, then a 4-inch air filter is better than a 1-inch air filter to improve air quality. Like length and width, thickness is an important part of sizing the oven filter and getting the right fit to optimize performance.
