A filter system having individual compartments, a removable filter rack in each compartment, and an array of filter elements positioned in candle housing that are moveable into and out of the filter racks. Each compartment has an independent set of dirty oil inlets, clean oil outlets, overflow outlets, and air purge inlets, and is fluidly separated from adjacent compartments by the interior walls of the frame. Each rack may be disengaged from the various pipes and removed from the frame without disengaging the racks in adjoining compartments. As a result, the filter elements may be serviced without having to take the entire system off-line.