The intent of this project is to replace the existing, indoor air handling unit, roof mounted condensing unit, and associated electric duct heaters with an air-cooled, low ambient variable refrigerant flow system (VRF) for both heating and cooling. The existing air handling unit and condensing unit will be demolished. All the electric duct heaters will be demolished or disconnected and abandoned in place. The low ambient (-18F) VRF system will be capable of simultaneously heating or cooling. The outdoor units will be located on ground level on the plan west side of the building. The associated refrigerant pipe will be routing into the building then split to the appropriate branch controllers located in the building. Special attention should be paid to the refrigerant routing, as some piping is required to ran across the roof to prevent disturbing the interior façade. Ducted and ductless fan coils will be installed to provided heating and cooling to the spaces. The condensate from these units will be pumped to the nearest acceptable termination point (roof, floor drain, or tail piece). For ventilation, a roof- mounted dedicated outdoors air system (DOAS) with heat wheel energy recovery and back-up electric heat will be installed. The unit return shall be ducted to the building return air plenum. The supply air with be connected to the existing supply air system and connect to each new VRV fan coil. Existing ductwork shall only be modified in areas where lay-in ceiling exists. All hard-lid ceiling is to remain. The new HVAC equipment shall be integrated into the JCI building controls system. The individual units shall be controlled by the manufacturer’s control system and each unit will be monitored by the JCI system. The existing electrical service panels will be removed and replaced. All other electrical work is concurrent with the mechanical scope to provide power to the afore mentioned equipment and systems.
