Yes the make 4" filter frames,pricey ,and you need enough space behind them unrestricted, them for the filter.
Will handle,means they increase ESP,and your duct system may be on the small side,so the increase will raise the ESP,beyond what the VS can safely deliver the required cfms.This can be reduced by using a larger filter ,if possible,or adding a return duct and grille,anything to reduce the ESP(static).
That is always an important bit of info.that should have been on the bid.
Originally posted by gmahler
they didn't give me a model no. on the bid.
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