1. Disconnect, remove, dispose off-site appropriately, and replace existing HVAC rooftop units (RTU) HVAC condenser unit located on roof of station building. 2. Contractor shall identify and propose comparable units that meet current industry standards for coolant and energy efficiency. Existing units zone into specific areas of the building. Contractor shall make recommendation of RTU products that is singular but can zone separately into the established areas, if such a product exists. New unit tonnage shall be commensurate to the demand required to heat and cool all spaces in the station facility. Contractors shall propose new units that also have the shortest lead time for delivery. New units shall have a manufacturer’s warranty of no less than five (5) years, preferably ten (10) years. 3. Contractor shall also replace heat pumps or existing heating systems if separate from RTU. 4. Contractor shall take extraordinary care to prevent structural compromise to roof system. 5. Contractor shall make evaluation of existing lines and electrical run. Contractor shall replace lines and upgrade electrical as necessary, but shall make proposal during bidding process. 6. Contractor shall replace existing thermostat sensors and controllers. 7. Install new unit and verify full optimal operation. 8. Contractor shall clean up after performing work.