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Can an F7/MERV 13 pollen filter be fitted to supply air outlet?

LordLiverpool | Posted in General Questions on

I have a Brink Renovent heat recovery ventilation system and I’ve opted to put an F7 pollen filter on it as well as the standard G4 filters. I think F7 filters are MERV 13 in the US. (The G4 filters are a thin foam-like material, whereas the F7 are like paper in a concertina form).

There are 2 G4 filters, one on the intake from the outside, and one on the outlet where the heated supply air comes out of the machine. I get the impression that the F7/MERV 13 is normally fitted to the intake (i.e. filtering before it gets to the machine), but is there any reason why this is so? Could it be fitted to the outlet on the other side instead? I ask because the G4 filters are washable and cheap and the F7 filters are *very* expensive and not washable. So I prefer to let the washable, cheap filters pick up as much dirt as possible so that I don’t have to change the F7 so often.

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  1. charlie_sullivan | | #1

    The advantage of a filter before the HRV is that dust can clog up the heat recovery core--either reducing its heat exchange efficiency or reducing air flow. The F7 probably does that better then the G4, but given that it's normally operated with just a G4 that should do the job and you should be fine with the F7 afterwards.

  2. LordLiverpool | | #2

    That's what I supposed. Would it be a good idea to put 2 G4s on the inlet side (they fit easily into the cartridge), or would that impede the air flow too much?

    1. woodguyatl | | #3

      As a rule of thumb, stacking identical filters rarely makes sense. This first will catch what it can and the second will not be able to catch what the first missed.

  3. jenniferz5 | | #4

    Can you provide feedback on your Brink system? It looks great, but there isn't much user information. Thanks.

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