Zehnder ComfoAir 200 Filter Set, ISO Coarse (G4), 2 pcs

Ideally, filters should be inspected monthly and given a light vacuum to remove dirt and debris. Filters will eventually become blocked with residual debris and should then be replaced. Generally, blocking will occur every 6 - 12 months depending on the location (near busy roads or inner city areas tend block more quickly than remote country settings).

Zehnder P/N 400 100 014