Can You Use a Smaller Furnace Filter?

Learn how to choose and install furnace filters correctly so they don't damage your HVAC system or reduce its efficiency.

Can You Use a Smaller Furnace Filter?

If you can't find a standard size filter that meets your needs, you may need to order a custom-sized air filter. The filters only work if air has to pass through them, as the filter has air resistance and a gap does not. If you leave a gap of 1, an excessive amount of air will flow through the hole, making the situation worse. The oven filters should fit properly, but there is no need to force them into place.

If you have to force the filter into its slot, it's likely too big. Forcing an incorrect filter size on a filter can cause it to bend, damage it, or reduce its ability to function properly. The filters are slightly smaller than their slot for easy replacement. Some HVAC units may require a filter with unique or unusual dimensions. In these cases, it is necessary to request a custom filter.

To answer the question: yes, you can cut an air filter if you know what you're doing and if the filters you're using don't weaken too much from the cut. Always follow the filter size guidelines to ensure you choose the correct size filter for your oven. Although it may seem daunting to dive into the world of air filters after researching your air conditioner or oven, it's essential to make sure you have the right one. If your boiler has an air filter in the return vent, changing the filter is easy, since you can do it from inside your home. Choosing the right type of filter for your oven along with the routine maintenance mentioned above will keep your costs low and your oven running smoothly.

While established deadlines serve as an excellent starting guide as to how often you should change your oven filter, there are some clear indicators that will let you know if the filter has become too clogged. When determining if this would be a good idea for your oven filter, keep in mind that the main purpose is to create a perfect fit that allows all air to pass easily and directly through the filter. From ensuring the right fit to choosing the right thickness and density for your needs, using the right filter will make a significant difference in the cost and efficiency of your oven. Look for where the return duct connects to the boiler and there should be a plate that covers the slot through which the air cleaner enters. So, regardless of your situation, you can calculate the size of the filter in your oven. Typically, you'll see filters with a MERV lower than 4 in residential ovens, window-mounted air conditioning units, or as a pre-filter in commercial units that need multiple filters. A clean, well-adjusted filter avoids a number of costly problems and will keep your oven running at its optimal capacity.

Not understanding these numbers often leads to consumers buying a filter that doesn't fit their heating or HVAC system. While filters with a higher MERV rating capture more particles from the air, a higher rating isn't necessarily the right choice for all ovens. Having to bend and force the filter into the boiler is a clear indicator that it is too large. When a filter that is too dense is used in an HVAC system that doesn't require that degree of resistance, it can restrict the air flow needed and cause the oven to work harder. When you change oven filters, the first thing to do is to know what size oven filter you have.