Oxigen is a sleek modern building that provides unique 24hr access to patrons, our task was to provide comfort air conditioning to 2 x large open gymnasium’s- the rpm stationary bike room- the crèche ( child care )- offices and entry reception. The gymnasium’s presented a design problem due to the decision to forego dropped ceilings so the heating and cooling had to cope with the entire space right to the underside of the roof some 8 meters high. The project included a large ventilation system to the locker rooms and toilets. The final design was to use large, roof top package units, for the gymnasium’s with exposed spiral duct providing the conditioned air, Two Temperzone OPA 960RKTBH 2 stage package units were selected with a combined heating and cooling capacity of 180 kilowatts ( around the equivalent of 12 x 6hp residential air conditioning units ). The design provided built in Economiser cycle which enables the system to shut down the air conditioning and supply outside air only when the temperature outside is lower than inside ( this can happen often in cooler weather with many people inside ) The remaining areas had normal dropped ceilings at 3 meters so split ducted systems were selected utilising two Toshiba models RAV-SM2802DT-2 and one Toshiba model RAVSM1403DT-A with a combined heating and cooling capacity of 42.5 kilowatts. The systems are all reverse cycle air conditioners. The ventilation system was designed using rectangular sheet metal ducting from the locker rooms terminating at a Pacific HVAC model RCV450-E roof centrifugal exhaust fan and the toilets used a PacificHVAC model RCV280-E roof centrifugal exhaust fan. The project was completed on time and on budget and now provides Western Sydney and the local Penrith residents air conditioning and comfort while training.