When it comes to air conditioning and HVAC units, each one has a specific size filter that allows it to work correctly and efficiently. Most of these units use standard-sized filters, but some require the purchase and installation of a custom-sized air filter. It's important to make sure the filter fits securely, but there's no need to force it into position. If you have to force the filter into its slot, it's probably too big and could cause it to deform, damage it, or reduce its ability to function properly.
The filters are slightly smaller than their slot for easy replacement. In cases where an HVAC unit needs a filter with unique or unusual dimensions, it is necessary to order a custom filter. Filter King offers hundreds of different filter sizes that can be used in various home systems, including the oven. If the return vent is on the roof, you may prefer a filter that has a slightly larger actual size, so that the filter doesn't fall on you when you open the vent.
For example, a size of 20x30x1 may appear on the filter label, but if you measure the filter, you will see that the actual size is smaller than the nominal air filter size of 20x30x1. Having several ventilation grilles solves this problem, but it also requires air filters in each vent to properly filter the air and prevent particles from entering the fan motor. Now that you know where to look for all replacement air filters, you're on your way to breathing better, cleaner air in your home. Starting from the actual sizes, round the measurements to the nearest whole number when you order new air filters. A high-quality filter that fits perfectly can keep the air cleaner and healthier, as it does not allow air to pass through the filter and return to indoor air.
For common brands of air conditioning systems, such as Goodman, Lennox, Trane, Rheem York, Coleman and Carrier, most standard air filter sizes will work. This tip from a Houzz discussion forum is worth mentioning: If you see a return duct that would fit a 2- or 4-inch air filter, but which has several 1-inch filters stacked on top of each other to fit in the slot, get rid of this configuration immediately. Not only does this help clean the air circulating around the house, but it also helps the central air unit work efficiently. If you change your air filters at the recommended intervals (usually 90 days), you won't have the chance of dust accumulating to the point of covering the ventilation grilles of the air conditioning vents.
You can find the recommended filter size for your unit model here, in the table titled “Find your air conditioner and oven filter by brand, model number, and size”. The best way to prevent dust from accumulating on the air conditioner intake vent cover is to replace the air filters regularly. HVAC service companies often offer air filter replacement services in addition to system repair and unit installation services.
