Best Solution for Fitting a Filter Cabinet Larger Than the Air Handler
A while back I hired a company to replace my old split AC & gas furnace system with a heat pump. From reading up I knew that a larger (thicker) air filter was a good idea for better indoor air quality and overall system performance, and so I asked the company to install one with the new air handler. The tech was annoyed and warned me that the larger filters are more expensive, but complied and installed a 16 x 25 x 4 Honeywell filter cabinet.
I’ve recently noticed that the filter cabinet is about 2″ larger than the air handler. As you can see from the attached photo, the tech just used foil tape to seal the gap in between.
My concern is that a thin layer of foil tape used to prevent unfiltered air from entering the coil and supply plenum seems risky. If the tape comes loose or gets damaged, the coil may become dirty and cause performance and longevity issues, and the indoor air quality would suffer.
What is the correct solution to this issue? Are filter cabinets supposed to be exactly matched (or undersized) to the size of the air handler cabinet, or is a site-made solution (sheet metal?) supposed to be applied?
Thanks for reading 🙂
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