CVP-ADAPT-F2F Noritz Female to Female Vent Adapter Noritz have changed the flue of all NEW DVC models to prevent condensate leakage where long vent runs are applied. With this change on the DVC model’s flue, the vent direction will be opposite from before. All existing DVC adjustable, straight and elbows will remain the same Only DVC termination vent pieces will change Note : Old Heaters with Old Venting: No changes or additions are necessary. These items will work together as always.Old Heaters with New Venting: This installation will need this adapter.New Heaters with New Venting: No changes or additions are necessary. These items will work together.New Heaters with Old Venting: This installation will need a Male-to-Male adapter piece, part number CVP-ADAPT-M2M.