1.03 RELATED SECTIONS: The following sections contain requirements that relate to this section.

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1 SECTION GAS FURNACE/DX COOLING UNIT PART 1 - GENERAL 1.01 RELATED DOCUMENTS A. Drawings and general provisions of contract including General and Supplementary Conditions of Division 1 of Specification sections apply to all work of this Division 15, as fully, as if repeated herein SUMMARY A. Units for installation indoors including appropriate sections as specified herein RELATED SECTIONS: The following sections contain requirements that relate to this section. A. Section Painting B. Section Air Coils C. Section Air Treatment Equipment D. Section Duct Accessories E. Section Sound Attenuators F. Section Controls and Instrumentation 1.04 REFERENCES A. NFPA 90A - Installation of Air Conditioning and Ventilation Systems. B. SMACNA - HVAC Duct Construction Standards. Coils. C. ARI Standard for Forced Circulation Air-Cooling and Air-Heating D. ANSI/UL Test Performance of Air Filter Units. E. AMCA Method for Publishing Sound Ratings for Air Moving Devices SUBMITTALS A. Submit as-built drawings and product data in accordance with Division 1

2 and section

3 B. As-built drawings shall show unit configuration in direction of airflow, and shall indicate assembly and unit dimensions. C. Product data shall indicate dimensions, weights, capacities, fan performance, motor electrical characteristics, and finishes of materials. D. Submit product data of filter sizes and quantities, filter performance, and filter frames. E. Submit manufacturer's installation instructions under provisions of Section F. Provide fan curves with specified operating point clearly plotted QUALITY ASSURANCE A. Air Handling Units: Product of manufacturer regularly engaged in production of components who issues complete catalog data on total product offering. B. Air Handling Units: Certify capacity, static pressure, fan speed, brake horsepower and selection procedures in accordance with ARI C. Air Coils: Certify capacities, pressure drops and selection procedures in accordance with ARI OPERATION AND MAINTENANCE DATA A. Submit operation and maintenance data under provisions of Section B. Include instructions for lubrication, filter replacement, motor and drive replacement, spare parts lists, and wiring diagrams DELIVERY, STORAGE, AND HANDLING A. Deliver products to site under provisions of Section B. Store and protect products under provisions of Section C. Store in clean dry place and protect from weather and construction traffic. Handle carefully to avoid damage to components, enclosures, and finish.

4 1.09 ENVIRONMENTAL REQUIREMENTS A. Do not operate units for any purpose, temporary or permanent, until ductwork is clean, filters are in place, bearings lubricated, and fan has been test run under observation EXTRA STOCK A. Provide two extra complete sets of all disposable filters. PART 2 - PRODUCTS 2.01 ACCEPTABLE MANUFACTURERS A. Gas Furnace/DX Cooling Units 2.02 GENERAL 1. Trane 2. McQuay 3. Carrier A. Any exceptions to the specifications must be clearly defined. The contractor shall be responsible for any additional expenses that may occur due to any exception made. B. Fabricate draw-through type air handling units suitable for the scheduled air pressure operation. C. Fabricate units with supply fan section, coil sections, filter section, supply plenum and return plenum as required. The entire unit shall sit on a factory fabricated structural C-channel base rail that can be anchored to the floor GAS FURNACE A. High-efficiency furnace with reliable 4-way multipoise design. The Carrier model 58MXA, available in 12 heat/airflow combinations and with the 4-way multipoise design, shall be installed in upflow, downflow or horizontal positions. Provide unit hot surface ignition (HSI) to ignite the burners directly. Hot surface ignition shall provide reliable start-up and operation.

5 Control of ignition, inducer and blower operation handled in 1 central printed circuit board. Status indicator on the control signals when a fault has occurred and identifies where the problem is. High efficiency is achieved by maximizing heat transfer. The model 58MXA uses 100% outdoor air for combustion in a sealed-combustion system, with 92% Annual Fuel Utilization Efficiency (AFUE). Polypropylene-laminated heat exchanger. The secondary heat exchange shall ensure that all available heat is properly transferred to the airstream. Using flow-through design, the secondary heat exchanger reduces pressure drop in the furnace. Heat exchangers shall be backed by a Limited Lifetime Warranty. Provide model 58MXA equipped for either left or right side connections. Blower speeds easily adjustable with speed-taps conveniently located on the control center. Inducer allows for more use of 2-in. vent and combustion-air piping, keeping installation costs low. B. Casing: One piece, seamless wrap-around construction of heavy, galvanized steel resists corrosion. C. Insulated Blower Compartment: The acoustical insulation reduces air and motor noise to promote quiet operation. D. Certification: The 58MXA units shall be A.G.A. and C.G.A design certified for use with natural and propane gases. The furnace is factoryshipped for use with natural gas. A.G.A/C.G.A listed gas conversion kit is required to convert furnace for use with propane gas. Unit efficiency is GAMA efficiency rating certified. Provide combustion-air and vent pipes which terminate through a side wall or through the roof with factoryauthorized vent termination kit. E. Blower Access Panel Switch: Shuts off all 115-v power through furnace components whenever blower access panel is opened. F. Hot Surface Ignitor: No pilot flame. Slow opening redundant gas valve will shut off gas to burners if 1 of the valves fails to close completely for any reason. The slow opening feature reduces start-up noise from rapid ignition. G. Insulation: Foil-faced insulation at heat exchanger section of the casing. H. Control Center: Microprocessor controls sequencing and furnace operation. Equipped with a component test feature and status indicator light to assist in troubleshooting. Microprocessor blower control times blower start after main burners ignite to eliminate cold air blowing into rooms.

6 I. Adjustable Blower Speed: For precise airflow selection of heating or cooling operations. J. Direct-Vent Sealed Combustion System: 100% outdoor air. Direct venting minimizes the possibility of chloride contamination which can result in heat exchanger corrosion. Direct venting also reduces air infiltration into the home. K. Serpentuff: Serpentuff coating, a patented polypropylene laminate is used on the secondary heat exchanger AIR-COOLED CONDENSER A. Totally Enclosed Fan Motor: Permanent-split-capacitor-type motors. B. Unit Design: Cooper tube, enhanced aluminum fin coil designed for optimum heat transfer. Vertical air discharge carries sound and hot condenser air up and away. Heat pump style drain pan for easy removal of water, dirt, and leaves. C. Model 38TRA combined with evaporator coils and blower packages to provide quiet, dependable comfort. Unit to be installed at ground level. D. External Service Valves: Both service valves are brass, back seating type with sweat connections. Valves are externally located so refrigerant tube connections can be made quickly and easily. Each valve has a service port for ease of checking operating refrigerant pressures. 1. Easy Serviceability: One access panel provides access to electrical control box and compressor. Removal of top gives access to coil. Removal of wire grille gives access to the fan motor. 2. Compressor: Provide scroll compressor motor protected with internal temperature- and current-sensitive overloads. For improved serviceability each compressor ( ) is equipped with a compressor terminal plug. 3. Sound Hood: A thick, sound dampening material wrapped around the compressor muffles operational noise. 4. Limited Warranty: Standard 1-year warranty on parts, with an additional 9-year warranty on compressor.

7 E. ACCESSORY DESCRIPTION AND USAGE 2.05 FILTERS 1. Ball Bearing Fan Motor. 2. Compressor Start Assist - Capacitor and Relay 3. Compressor Start Assist - PTC 4. Crankcase Heater 5. Cycle Protector 6. Evaporator Freeze Thermostat 7. Filter Drier 8. High-Pressure Switch 9. Liquid-Line Solenoid Valve (LSV) A. Provide factory filter section of the same construction and finish as unit casing with filter guides and hinged, removable double wall access doors with automotive style gasket for minimum leakage for filter removal. Blockoffs shall be provided by the unit manufacturer as required to prevent air bypass around filters. Filters shall be face loaded. B. Provide filter media in accordance with Section "Air Treatment Equipment (Filters)" INSULATION A. Unit located indoors shall be factory insulated with one-inch 1-1/2 pound density mat-faced or vinyl-coated insulation with tapped or sealed edges. All connecting channels shall be insulated to prevent sweating OUTSIDE AIR/RETURN AIR DAMPERS A. Outside air/return dampers shall be provided to modulate the volume of outside and return air. Dampers shall be of airfoil design and shall be either parallel or opposed blade type with metal compressible jamb seals and extruded vinyl blade edge seals on all blades. Blades shall rotate on stainless steel sleeve bearings. Maximum damper blade length shall be 60- inches. Leakage rate shall not exceed five cfm/square foot at one-inch wg and nine cfm/square foot at four-inches wg. Damper operators shall be electrical and shall be by the mechanical contractor.

8 PART 3 - EXECUTION 3.01 INSTALLATION A. Install components in accordance with manufacturer's instructions. **END OF SECTION**