WATER-COOLED HELICAL ROTARY CHILLER

Transcription

1 WATER-COOLED HELICAL ROTARY CHILLER 1.0 GENERAL REQUIREMENTS 1.1 Application. This technical specification applies to equipment and materials furnished and installation work performed by the Contractor. 1.2 Jobsite: The State of Florida, Dept. of Children and Families (Owner) is procuring one replacement chiller for the following state-owned building: Emmett S. Roberts Building 5920 Arlington Expressway, Jacksonville, FL Site Contact: Chuck Johnson, Tel. (904) Alternate Site Contact: Larry Lemelin, Tel. (904) Scope of Work. Work included under this specification includes: A. Furnishing one new water-cooled helical rotary water chiller as specified herein. B. Removal and disposal of existing Chiller #2 and starter/control cabinet. C. Installation of the new chiller, including chilled water and condenser water piping connections inside the mechanical room; re-routing and insulating chilled water piping inside the mechanical room; installation of water flow switches; and, verification of proper water treatment for the new chiller. D. Providing electrical power and control wiring connections (including water flow interlocks), and building automation system (BAS) programming to interface with the new chiller. 1.4 System Description. The chiller to be replaced (Chiller #2) fits into the HVAC systems as follows: A. Chiller evaporators are piped in series ( T=5 F each per original design). CHW flows sequentially through chillers at 600 gpm, leaving Chiller #2 at 44 F supply setpoint. B. Each chiller has its own cooling tower and condenser water pump. Condenser water flow is 450 gpm, designed for 85 F supply water under full-load conditions. C. Each chiller reports its operational parameters to an existing Trane Tracer Summit building automation system (BAS). The BAS operator, in turn, is capable of starting and stopping each chiller (manually or by daily schedule), and can remotely adjust the chilled water supply temperature for each chiller. 1.5 Documentation. The Contractor shall submit the following: Technical Specification -- Page 1

2 A. Chiller shop drawings shall be submitted and approved by the Owner before equipment is ordered. Shop drawings shall indicate components and their assembly; control features; weights and dimensions; and, operational and performance data. 1. Operational data shall include: rated capacities, refrigerant type, electrical requirements, performance specifications, control system operation, and other such information. 2. Performance data (energy input versus cooling load output) based on ANSI/AHRI Standard 550/590 conditions, shall be plotted from 10 percent to 100 percent of full load. B. Shop drawings for installation materials shall be submitted before ordering. Submittals shall include diagrams showing intended routing of new conduit above the floor, and new chilled water piping routing to accommodate 2-pass evaporator configuration. C. Performance test results shall accompany or precede chiller delivery to the jobsite. (Performance test shall be conducted by the chiller manufacturer in accordance with ANSI/AHRI Standard 550/590.) D. Three copies of operating and maintenance instructions shall be provided to the Owner upon completion of the job. E. Copies of both the Manufacturer's warranty and the Contractor's warranty shall be delivered to the Owner at completion of the job. 1.6 Coordination. All on-site activity shall be coordinated with the Site Contact or his designee. 1.7 Installation work shall be conducted such that system downtime is minimized. 1.8 Acceptance. Work not conforming to specified requirements, or any work for which approval has not been obtained, shall be rejected. 1.9 Warranty. Provide a one-year Contractor s Warranty on all installation workmanship and materials. 2.0 ACCEPTABLE PRODUCTS 2.1 The Contractor shall furnish one Trane Model RTHD water-cooled helical rotary water chiller with Adaptive Frequency Drive, B2-B2-B2 configuration (Product Version #167), conforming to Owner s Basis of Design. 2.2 Basis of Design. Specified unit shall be certified in accordance with ANSI/AHRI Standard 550/590 at the following conditions: Technical Specification -- Page 2

3 Trane Model RTHD w/ Adaptive Frequency Drive Compressor/Evaporator/Condenser B2-B2-B2 Configuration Evaporator Leaving water temp 44 F Evaporator Entering water temp 51.7 F Evaporator Flow (gpm) 600 gpm Evaporator passes 2 Evaporator pressure drop 7.00 ft. Condenser Entering water temp 85 F Condenser Leaving water temp 97.4 F Condenser Flow (gpm) 450 gpm Condenser passes 2 Cond pressure drop (max) 8.30 ft. Full Load Capacity Tons Full Load Efficiency kw/ton NPLV kw/ton IPLV kw/ton Electrical 480v / 3ph / 60Hz Minimum Ckt. Ampacity (MCA) amperes Max. Overcurrent Protection (MOCP) 400 amperes Factory Refrigerant Included R-134A Dimensions 125.4"L x 64.9"W x 74.4"T 2.3 Factory-supplied Accessories. The chiller manufacturer shall provide each of the following features, without exception: Factory Adaptive Frequency Drive Factory mounted circuit breaker Factory insulation (all cold surfaces) 7" Color touch screen control panel LonMark control interface Factory charge of R-134A refrigerant Shrink wrap packing for shipment Two (2) flow switches (shipped loose for contractor installation) Factory start-up 5 year factory warranty - Whole unit - including parts, labor & refrigerant 2.4 Performance requirements. The Manufacturer will be required to conduct a factory performance acceptance test to verify performance figures submitted with the shop drawings. Chiller performance shall be tested in accordance with ANSI/AHRI Standard 550/590. Certified performance shall be equal to performance claimed by the Manufacturer. 2.5 Condition of Equipment Furnished. The furnished equipment shall be shipped, delivered, and set in place, free of internal and external physical damage. The owner shall have the right to refuse any equipment set in place with obvious physical damage. Technical Specification -- Page 3

4 2.6 Internal control features. The new chiller shall be furnished with an integral programmable control system with display panel front. Panel shall feature a display readout for pressures, temperatures, setpoints, etc., plus keypad(s) for programming setpoints and calling up data for display. Control system shall provide the following key features, as a minimum: A. Programmable setpoints: leaving chilled water temperature, electrical demand limit. B. Selectable display of operating parameters: Chilled water temperatures, condenser water temperatures, refrigerant pressures, percent motor current draw, oil pressure, operating hours. C. Display of safety/cycling shutdown messages providing the day and time of shutdown, cause of shutdown, and type of restart required. D. A time delay to prevent compressor restart within fifteen minutes of shutdown. E. Anti- single phase and phase reversal protection. F. High condenser refrigerant pressure cutout. G. Low evaporator refrigerant temperature cutout. H. Low oil pressure and high oil temperature trips. I. Waterflow interlocks (to prove chilled water and condenser water flow via external flow switches) as a condition for chiller operation). 3.0 EXECUTION 3.1 Release for Manufacture. Contractor shall obtain Owner approval of shop drawing submittal before ordering any equipment. (Release for Manufacture is contingent upon release of appropriated funds by the Office of the Governor.) 3.2 Demolition. The Contractor shall remove existing Chiller #2 and dispose offsite. The Contractor shall also remove the chiller starter/control cabinet (mounted on a separate concrete pad behind the chiller), preserving the underfloor conduit stub coming up through the pad for pulling new power conductors. 3.3 Chiller delivery to Jobsite. The Contractor shall provide offloading, crane and rigging as needed to unload the delivery truck, and shall assure protected storage if the chiller is not immediately set in place on the mounting pad. (The Owner, with advance notice, will make storage space inside the loading dock available for temporary storage of the new chiller on the date of delivery to the jobsite.) Provide the Owner with documentation of certified performance test results. Technical Specification -- Page 4

5 3.4 Installation of new equipment. The new chiller shall be set on the equipment pad vacated by the old machine. The Contractor shall provide loading, lifting, disassembly/reassembly, and rigging as needed to install the new chiller on the equipment pad. Follow Manufacturer s procedures for mechanical installation (Trane Document #RTHD-SVX01D-EN). The Contractor is responsible for restoring & reconnecting building fixtures requiring temporary relocation to clear a travel path for chiller equipment. 3.5 Pipe Fabrication and Installation: A. Modify existing piping & valves as necessary to reconnect to new chiller. Connections shall be in accordance with approved shop drawings. B. Per the original design, Chiller #2 had a 1-pass evaporator with left-hand inlet and right-hand outlet. Shop drawings should describe a rerouting of chilled water piping to accommodate 2-pass evaporator connections. Recommended: Left-hand inlet & outlet connections, with CHW outlet piping routed through space vacated where existing starter/control cabinet was removed (see Paragraph 3.2 above). Coordinate with new power conduit routing (see Paragraph 3.7B below). C. Make piping layout and installation in the most advantageous manner possible with respect to headroom, valve access, opening and equipment clearance for other work. Give particular attention to piping in the vicinity of equipment. Preserve the maximum access to various equipment parts for maintenance. D. Chilled water and condenser water piping shall be Schedule 40 black steel per ASTM A120 Gr. A or ASTM A53 Gr. A or B. Fittings shall be Schedule 40 black steel seamless butt-welded per ASTM A234 and ANSI B16.9 to match pipe wall thickness. Flanges shall be ANSI 16.5, 150-lb. rated, black steel, flat-faced, welding neck to match pipe wall thickness. E. Fabricate sections having butt-welded joints offsite, to the greatest extent possible, to minimize welding activity inside the building. F. Install pipe neatly, free from unnecessary traps and pockets. Work into place without springing or forcing. Align piping to eliminate strain on evaporator and condenser heads. Use fittings to make all changes in direction (i.e., field bending and mitering are prohibited). Make reducing connections with reducing fittings only. Make all connections to equipment using flanged joints or unions. Arrange piping to permit removal of evaporator and condenser heads with minimal disassembly of piping. G. Flush dirt, scale and other foreign matter from inside piping before tying in sections, fittings, valves or equipment. H. Whenever practical, install piping close to walls, ceilings and columns, so as to minimize space requirements. Provide proper clearances for pipe insulation, for offsets, and for operation and maintenance of fittings. Technical Specification -- Page 5

6 I. Support pipe adequately to maintain line and grade, with due provision for expansion and contraction. Support piping so that no piping weight is supported by equipment. J. Provide anchors as required. Use pipe anchors consisting of heavy steel collars with lugs and bolts for clamping to pipe and attaching anchor braces. Install anchor braces in the most effective manner to secure the desired results. Do not install supports, anchors or similar devices where they will damage construction during installation or because of the weight or the expansion of the pipe. If necessary, insulate anchors sufficiently to prevent moisture condensation problems. K. Install 3/4" drain valves at all low points of water piping systems so that these systems can be drained completely. L. Install Factory-provided flow switches in the chilled water and the condenser water piping per Manufacturer s instructions. M. Clean or flush piping systems thoroughly. Purge pipe of construction debris and contamination before placing the systems in service. Remove temporary piping and jumpers when cleaning and flushing is complete. Use temporary strainers on initial start-up, to protect the new shell-andtube exchangers on the new chiller. Remove temporary strainers before completion of job. N. Furnish suitable water treatment for the chilled water loop. 3.6 Pipe Insulation. Provide cellular glass piping insulation on all new chilled water piping. A. Cellular glass insulation shall be preformed, water retardant, closed cell composition, complying with ASTM C 552, Specification for Cellular Glass Thermal Insulation. Thermal conductivity k rating shall be less than 0.30 Btu-in/hr ft² F at 75 F. Flame-spread/smoke-developed ratings shall be 0/0. Equal to Pittsburgh-Corning Foamglas. B. Pipe jacketing and fitting covers shall be aluminum, minimum inch thick, with laminated or baked moisture retardant. C. Insulate with bore-coated prefabricated cellular glass pipe insulation. Apply thickness of insulation equal to the existing insulation to which it is joined. Coat joints with joint sealant and secure each new section with not less than two 16-gauge stainless steel wires. Finish with jacketing secured with straps. Finish elbows and fittings with mastic reinforced with fabric, or finish with fitting covers. D. Apply insulation and finish materials in strict accordance with all manufacturers recommendations. 3.7 Electrical Hookup. The Contractor shall provide a complete electrical installation, as follows: Technical Specification -- Page 6

7 A. All wiring shall be copper, sized per NEC. B. Provide properly-supported rigid conduit to the chiller for power wiring. Extend new conduit to the chiller from the conduit stub left penetrating through pad where existing starter/control cabinet was removed. (See Paragraph 3.2 above.) Verify grounded continuity of entire conduit run, or alternatively, provide an equipment grounding conductor sized per NEC Article 250 (Table ) within the conduit. C. New power conductors shall be minimum 250 kcmil, Type THW, rated 75 C. Pull new power conductors through new conduit in a continuous run from existing fused switch. Verify existing or provide new 400-amp fuses in existing fused disconnect. D. The chilled water and condenser water flow switches shall be wired to internal controls per Manufacturer's instructions. Flow switches shall be checked to confirm that they are installed and wired correctly, and that they are functioning properly to prove condenser- and chilled-water flow. E. Contact Trane Factory Service to reconnect disconnected BAS wiring. 3.8 Start-Up and test. Contact Trane Factory Service for factory startup. 3.9 Final acceptance. The completed installation shall be inspected by the Owner s designee. Final payment shall not be authorized until: A. All building fixtures temporarily relocated to clear a path for equipment are fully restored & reconnected. B. All noted deficiencies are corrected. C. All required documentation has been delivered to the Owner. D. Necessary water treatment systems are in place and functioning. E. Full BAS control of chiller operation and chilled water setpoint is tested and confirmed. Technical Specification -- Page 7