SECTION HEAT PUMPS

Transcription

1 SECTION HEAT PUMPS PART 1 GENERAL 1.1 SUMMARY A. Section Includes: 1. Packaged rooftop heat pumps. 1.2 REFERENCES A. American Society of Heating, Refrigerating and Air-Conditioning Engineers: 1. ASHRAE Energy Standard for Buildings Except Low-Rise Residential Buildings. 1.3 DEFINITIONS A. Coefficient of Performance (COP), heat pump, heating - Ratio of rate of heat delivered to rate of energy input, in consistent units, for complete heat pump system, including compressor and, if applicable, auxiliary heat, under designated operating conditions. B. Energy Efficiency Ratio (EER) - Ratio of net cooling capacity in Btu/h to total rate of electric input in watts under designated operating conditions. C. Heating Seasonal Performance Factor (HSPF) - Total heating output of heat pump during its normal annual usage period for heating (in Btu) divided by total electric energy input during the same period. D. Seasonal Energy Efficiency Ratio (SEER) - Total cooling output of an air conditioner during its normal annual usage period for cooling (in Btu) divided by total electric energy input during the same period (in Wh). 1.4 SUBMITTALS A. Shop Drawings: Indicate dimensions, rough-in connections, and duct connections of manufactured products and assemblies. Indicate electrical service with connection requirements. B. Product Data: Submit drawings indicating capacity, weights, electrical characteristics and connection requirements. Indicate electrical characteristics. C. Manufacturer's Installation Instructions: Submit assembly, support details, connection requirements, and include start-up instructions. D. Manufacturer's Certificate: Certify products meet or exceed specified requirements

2 1.5 CLOSEOUT SUBMITTALS A. Project Record Documents: Record actual locations of controls separate from units. B. Operation and Maintenance Data: Submit manufacturer's descriptive literature, operating instructions, installation instructions, and maintenance and repair data. 1.6 QUALITY ASSURANCE A. Air Cooled Equipment: 1. Cooling Performance Requirements: Conform to minimum SEER [EER] prescribed by ASHRAE 90.1 when tested in accordance with ARI 210/ Heating Performance Requirements: Conform to minimum COP prescribed by ASHRAE 90.1 when tested in accordance with ARI 210/240. B. Perform Work in accordance with the City of Atlanta Department of Aviation standards. 1.7 QUALIFICATIONS A. Manufacturer: Company specializing in manufacturing products specified in this section with minimum three years of experience. B. Installer: Company specializing in performing Work of this section with minimum three years of experience approved by manufacturer. 1.8 PRE-INSTALLATION MEETINGS A. Convene minimum one week prior to commencing work of this section. 1.9 DELIVERY, STORAGE, AND HANDLING A. Accept heat pump units on site in factory packaging. Inspect for damage. B. Protect heat pump units from damage by providing temporary covers until construction is complete in adjacent space. Protect rooftop heat pump units from damage by storing off roof until roof mounting curbs are in place FIELD MEASUREMENTS A. Verify field measurements prior to fabrication WARRANTY A. Furnish five year manufacturer s warranty for Compressors

3 1.12 MAINTENANCE SERVICE A. Furnish service and maintenance of packaged heat pump roof top units for one year from Date of Substantial Completion. Include maintenance items as shown in manufacturer's operating and maintenance data, including filter replacements, fan belt replacement, and controls checkout and adjustments. Furnish 24-hour emergency service on breakdowns and malfunctions EXTRA MATERIALS A. Furnish one set of filters for each unit. PART 2 PRODUCTS 2.1 ROOFTOP HEAT PUMPS A. Manufacturers: 1. Equal to Carrier Corp. B. Product Description: Roof mounted, self-contained, packaged, factory assembled and pre-wired, consisting of cabinet and frame, supply fan, supplementary electric heating elements, reversing valve, controls, air filters, compressor, refrigerant coils and fans. C. Fabrication: 1. Cabinet: Constructed of phosphated, zinc-coated prepainted steel, access doors or removable access panels. 2. Insulation: one inch thick neoprene coated glass fiber with edges protected from erosion. D. Supply Fan: Forward curved centrifugal type, resiliently mounted, high efficiency motor. E. Air Filters: 1 inch thick glass fiber disposable media in metal frames. F. Roof Mounting Curb: 14 inches high, galvanized steel, channel frame with gaskets, nailer strips. G. Electric Heating Coil: 1. Electric heating coil shall be open--wire type, adequately supported and insulated with ceramic bushings. 2. Controls: Confirm supply fan is operating before electric elements are energized. Operate electric heater in when outdoor ambient is too low to maintain space thermostat setting with compressor operation. H. Space Supply Air Coil: 1. Copper tube aluminum fin coil assembly with galvanized drain pan and connection. 2. Capillary tubes or thermostatic expansion valves for units of 10 tons capacity and less, and thermostatic expansion valves and alternate row circuiting for units 12 tons cooling capacity and larger

4 I. Compressor: 1. Fully hermetic, 2-stage scroll compressors with factory--installed vibration isolation. 2. Compressor Protection: Defrost control shall protect compressor by preventing short cycling. J. Outdoor Coil: 1. Copper tube aluminum fin coil assembly with subcooling rows and coil guard. 2. Direct drive propeller fans, motor overload protection, wired to operate with compressor. Furnish high efficiency fan motors. K. Mixed Air Casing: 1. Dampers: Manual outside and return air dampers for fixed outside air quantity. L. Operating Controls - Single Zone Units: 1. Electric solid state microcomputer based room thermostat, located as indicated on Drawings. 2. Room thermostat incorporating: a) Automatic switching from cooling to heat pump heating to supplemental electric heating. b) Instant override of set point for continuous or timed period from one hour to 31 days. c) Short cycle protection. d) Programming based on weekdays, Saturday and Sunday. e) Switch selection features including imperial or metric display, 12 or 24-hour clock, keyboard disable, remote sensor and fan-on-auto. M. Operating Controls: 1. Terminal strip on unit for connection of operating controls to remote panel. Control for two stages of heating and two stages of cooling. 2. Remote mounted fan control switch (on-auto). 3. Night control energized by central time clock to lock out refrigeration, stop supply air fan for night and unoccupied operation. N. Operating Controls - Variable Volume Units: 1. Control cooling by controlling fan speed and cycling compressor. PART 3 EXECUTION 3.1 EXAMINATION A. Verify roof curbs are installed and dimensions are as instructed by manufacturer. B. Verify electrical rough-in is at correct location

5 3.2 INSTALLATION A. Install rooftop units on factory built roof-mounting curb with watertight enclosure to protect ductwork and utility services. Install roof mounting curb level. B. Connect indoor units to supply and return ductwork with flexible connections. C. Install accessories furnished loose for field mounting. D. Install electrical devices furnished loose for field mounting. E. Install control wiring between unit control panel and field mounted control devices. 3.3 MANUFACTURER'S FIELD SERVICES A. Furnish initial start-up and shutdown during first year of operation, including routine servicing and checkout. 3.4 CLEANING A. After construction is completed, including painting, clean exposed surfaces of units. B. Vacuum clean coils and inside of cabinets. C. Touch up marred or scratched surfaces of factory finished cabinets, using finish materials furnished by manufacturer. D. Install new throwaway filters in units after Substantial Completion. 3.5 DEMONSTRATION A. Demonstrate unit operation and maintenance. B. Furnish services of manufacturer's technical representative for one hour to instruct Owner's personnel in operation and maintenance of units. Schedule training with Owner, provide at least 7 days notice to Architect/Engineer of training date. END OF SECTION