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DocuSign Envelope ID: B94F2D40-3B3C-47A7-86C2-6F1 B4F92C62C <br /> Orange County Emergency Services Building Construction Documents <br /> 1. R-410A refrigerant <br /> 2. Variable capacity compressor with 10-100% capacity control <br /> 3. Direct drive supply fans <br /> 4. Double wall cabinet construction <br /> 5. Insulation with a minimum R-value of 13.0 <br /> 6. Stainless steel drain pans <br /> 2.02 ROOFTOP UNITS <br /> A. General Description <br /> 1. Packaged rooftop unit shall include compressors, evaporator coils, filters, supply fans, <br /> dampers, air-cooled condenser coils, condenser fans, reheat coil, exhaust fans, and unit <br /> controls. <br /> 2. Unit shall be factory assembled and tested including leak testing of the DX coils, pressure <br /> testing of the refrigeration circuit, and run testing of the completed unit. Run test report shall <br /> be supplied with the unit in the service compartment's literature pocket. <br /> 3. Unit shall have decals and tags to indicate lifting and rigging, service areas and caution areas <br /> for safety and to assist service personnel. <br /> 4. Unit components shall be labeled, including refrigeration system components and electrical <br /> and controls components. <br /> 5. Estimated sound power levels (dB) shall be shown on the unit ratings sheet. <br /> 6. Installation, Operation, and Maintenance manual shall be supplied within the unit. <br /> 7. Laminated color-coded wiring diagram shall match factory installed wiring and shall be affixed <br /> to the interior of the control compartment's hinged access door. <br /> 8. Unit nameplate shall be provided in two locations on the unit, affixed to the exterior of the unit <br /> and affixed to the interior of the control compartment's hinged access door. <br /> B. Construction <br /> 1. All cabinet walls, access doors, and roof shall be fabricated of double wall, impact resistant, <br /> rigid polyurethane foam panels. <br /> 2. Unit insulation shall have a minimum thermal resistance R-value of 13. Foam insulation shall <br /> have a minimum density of 2 pounds/cubic foot and shall be tested in accordance with ASTM <br /> D 1929-11. <br /> 3. Unit construction shall be double wall with G90 galvanized steel on both sides and a thermal <br /> break. Double wall construction with a thermal break prevents moisture accumulation on the <br /> insulation, provides a cleanable interior, prevents heat transfer through the panel, and <br /> prevents exterior condensation on the panel. <br /> 4. Unit shall be designed to reduce air leakage and infiltration through the cabinet. Cabinet <br /> leakage shall not exceed 1% of total airflow when tested at 3 times the minimum external <br /> static pressure provided in AHRI Standard 340/360. Panel deflection shall not exceed L/240 <br /> ratio at 125% of design static pressure, at a maximum 8 inches of positive or negative static <br /> pressure, to reduce air leakage. Deflection shall be measured at the midpoint of the panel <br /> height and width. Continuous sealing shall be included between panels and between access <br /> doors and openings to reduce air leakage. Piping and electrical conduit through cabinet <br /> panels shall include sealing to reduce air leakage. <br /> 5. Roof of the air tunnel shall be sloped to provide complete drainage. Cabinet shall have rain <br /> break overhangs above access doors. <br /> 6. Access to filters, dampers, cooling coils, reheat coil, exhaust fans, energy recovery wheels, <br /> compressors, and electrical and controls components shall be through hinged access doors <br /> with quarter turn, zinc cast, lockable handles. Full length stainless steel piano hinges shall be <br /> included on the doors. <br /> 7. Exterior paint finish shall be capable of withstanding at least 2,500 hours, with no visible <br /> corrosive effects, when tested in a salt spray and fog atmosphere in accordance with ASTM B <br /> 117-95 test procedure. <br /> 8. Units with cooling coils shall include double sloped 304 stainless steel drain pans. <br /> 9. Unit shall be provided with horizontal discharge and return air openings. All openings through <br /> the base pan of the unit shall have upturned flanges of at least 1/2 inch in height around the <br /> opening. <br /> 10. Unit shall include lifting lugs on the top of the unit. <br /> PDC Project 18102 100 PERCENT OUTSIDE AIR 23 74 00- 2 <br /> 12/17/2018 PACKAGED DX UNIT <br />