An assembly of a compressor for pressurizing a fluid includes a main housing having a portion being substantially planar. The housing defines at least two parallel intersecting bores. At least two rotors are journaled for rotation within the bores. A plurality of vent channels in the main housing extend outwardly from at least one bore through the portion being substantially planar. The vent channels are configured for the fluid to flow through the vent channels. A slide valve assembly is operably connected to the housing proximate the plurality of vent channels. The slide valve assembly has a valve plate wherein the valve plate has a substantially planar side that is sealingly engaged with the planar portion of the main housing. The valve plate is positioned into one of a plurality positions relative to the vent channels.