Patent ID: 7992723

Claim:
A method of filtering fluid comprising: a) forcing fluid through an inlet into a chamber containing a filter cartridge comprising filter media and a housing surrounding the media, the housing comprising a generally tubular diffuser member having two end caps, a length and an outlet, and being sealed such that all fluid flow out of the outlet must first enter the cartridge and pass through the media, the generally tubular diffuser member comprising louvered openings comprising a plurality of stamped tabs extending inwardly and towards a first end of the cartridge and a plurality of stamped tabs extending inwardly and toward a second end of the cartridge opposite the first end, the fluid flowing through the inlet and impinging directly on the filter cartridge; b) passing the fluid into the cartridge through multiple inlet flow paths configured so that fluid impinging on the cartridge is diffused as it enters the cartridge, said multiple inlet flow paths being provided by said louvers and being spaced along the length of the housing; c) filtering the fluid through the filter media inside the cartridge after the fluid has passed through said multiple inlet flow paths; and: d) passing filtered fluid out of the cartridge through a cartridge outlet in fluid communication with a chamber outlet.