Best location to place an air filter?

Q: There are two possible locations to put an air filter for my HVAC system. 1. ceiling return grill 2. furnace blower unit in the attic

Currently there is no filter at the blower unit. I have been putting Filtrete 1900 at the return grill because it’s easier to change and I assume that will keep the return duct cleaner.

Recently a HVAC guy commented I will have better filtration if the filter is closer to the blower (he suggested #2 location)

  1. Can I put two filters in my system – one at the return gill (a cheap one) and one at the blower (Filtrete 1900)? or that will create too much airflow restriction?
  2. If I should only have one filter, which location will be best? – indhtgc

A: I would keep the filter where it is. In my experience, filters that are installed directly at the unit or even inside the unit can be a pain to replace. The return air filter grille is much more convenient.

And no you don’t want to double filter it. That just puts unnecessary stress on the motor because it has to work harder to overcome two different filters instead of one. – Cobra449