York HVAC Catalogue 2018 EN 2019 EN | Page 152

Upflow supply (OPA-OPU models) Standard version with front air intake and upflow air delivery. Front air intake and front air outlet delivery with distribution plenum with adjustable grilles. Bottom air intake with raised floor support, blind front panel and upflow air delivery. Special versions “Water to air free cooling”: using renewable energy sources ‘Two Sources’ option utilising excess energy from building HVAC systems YC-OPA…/FC, YC-UPA…/FC air conditioners are equipped with a “Free cooling” system consisting of an additional chilled-water cooling coil integrated in the aluminium fins of the unit’s direct expansion one, with a three-way modulating valve controlled by the controller. As long as the outside conditions allow the water to respond totally or partially to the cooling request, the controller cuts out or minimises the compressors’ intervention, so reducing substantially the energy consumption. This system consists of the same chilled-water cooling coil as the “Free cooling”, but fed by the building water chiller. A built in frigorific circuit enters in operation in case of lack of chilled water. The result is the maximum security or a remarkable reduction of both consumption and running costs. This system can also use the direct-expansion coil circuit as primary cooling source and, in case of an emergency, the chilled-water coil connected with the tap water network. The “Two Sources” version is available for units with direct expansion circuit YC-OPA…./TS, YC-UPA…./TS as well as units with built in water cooled condenser (accessory) and with double chilled water coil YC-OPU…/TS, YC-UPU…/TS: one for district water and the other for tap water or water from a chiller (emergency). The water cooled condensers of the frigorific circuit are equipped with a pressostatic system for the regulation of the condensing pressure (flooding valves). The pumps and the expansion tank are not included in Johnson Control’s supply. The system widely uses the outdoor air—a renewable energy source—in lieu of or in addition to the mechanical cooling. 152