My air handler is supported by 2x4's which partially cover the filtered intake. I'd say there's 5-6" of blockage over the 21.5" filter size opening. Old air handler replaced after 12 years (due to outside coils leaking) was installed like this. I asked my contractor to fix this (twice) before installing a new unit, but they did not.
Is this going to negatively affect the performance or longevity of my split-system unit? Which parts will be affected? What is the proper method of supporting an air handler in a closet like this?