DENVER PUBLIC SCHOOLS DESIGN AND CONSTRUCTION STANDARDS This Standard is for guidance only. SECTION PUMPS

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1 PART 0 A/E INSTRUCTIONS 0.01 Design Requirements A. Pumping system design 1. A primary-secondary pumping system is preferred. Redundant pipes are required for chillers and boilers. 2. Select pumps to operate at optimum efficiency. 3. Base friction head calculations on Hydraulic Institute Standards for: a) Chilled water systems: 15-year-old-pipe. b) Hot water systems: 15-year-old pipe. c) Steam condensate: 15-year-old pipe. 4. When pump redundancy is required, provide 100% stand-by pumping (with check valves) with automatic change-over. 5. Select pump motor as non-overloading over the entire pump curve shown by the manufacturer. Consider option of pump operation reset based on reference temperature. 6. Specify pumps with separate pump and motor shafts and replaceable couplings for all but cartridge pumps. 7. Mechanical shaft seals shall be specified. Gland seals are not acceptable. B. Base-mounted water pumps 1. For primary pumping applications, split case centrifugal pumps are preferred over end-suction pumps. 2. Mechanical seals are required. Gland seals are not acceptable. 3. Specify complete flushing arrangement for mechanical seals and packing. 4. Specify double row outboard ball bearings on horizontal split-case pumps. 5. Specify vent and drain plugs and pressure gauge tappings on pump casings. 6. Specify guard on coupling. C. Electric steam-condensate return pumps 1. Specify packaged duplex pumps or steam-powered pumps. 2. Manual lead-lag alternator for duplex pumps. 3. Electrical float switch to bring on second pump if flow too great for one pump for duplex pumps. 4. Audible alarm activated when either pump fails (duplex pumps). 5. Specify deep sump type where adequate condensate cooling to avoid cavitation of pumps is not practical. 6. Provide a condensate cooler to avoid pump cavitation if condensate receiver is not big enough to achieve adequate cooling. PART 1 GENERAL 1.01 SUBMITTALS A. Product Data: 1. Pumps B. Shop Drawings: 1. Product Data: Include certified performance curves and rated capacities; shipping, installed, and operating weights; furnished specialties; final impeller dimensions; and accessories for each type Page 1 of 6

2 of product indicated. Indicate pump's operating point on curves. If parallel pumping is used, provide parallel pump operating curve data. 2. Show pump layout and connections. Include Setting Drawings with templates for installing foundation and anchor bolts and other anchorages. 3. Prefabricated Pieces C. Operation and Maintenance Data: 1. Operating and maintenance procedures QUALITY ASSURANCE A. UL Compliance: Fabricate and label pumps to comply with UL 778, "Motor-Operated Water Pumps," for construction requirements. B. Retain paragraph below to allow drawing details based on one manufacturer's product to establish requirements and still allow competition. Revise to identify specific proprietary system or indicate on drawings. Correlate with Division 1 requirements. C. Product Options: drawings indicate size, profiles, connections, and dimensional requirements of pumps and are based on the specific types and models indicated. Other manufacturers pumps with equal performance characteristics may be considered. Refer to Division 1 Section "Substitutions." D. Regulatory Requirements: Fabricate and test steam condensate pumps to comply with HI , "Centrifugal Pumps for Nomenclature, Definitions, Application and Operation," and HI 1.6, "Centrifugal Pump Tests." E. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, Article 100, by a testing agency acceptable to authorities having jurisdiction DELIVERY, STORAGE, AND HANDLING A. Manufacturer's Preparation for Shipping: Clean flanges and exposed machined metal surfaces and treat with anticorrosion compound after assembly and testing. Protect flanges, pipe openings, and nozzles with wooden flange covers or with screwed-in plugs. B. Store pumps in dry location. C. Retain protective covers for flanges and protective coatings during storage. D. Protect bearings and couplings against damage from sand, grit, and other foreign matter. E. Comply with pump manufacturer's written rigging instructions COORDINATION A. Coordinate size and location of concrete bases. Cast anchor-bolt inserts into bases. Concrete, reinforcement, and formwork requirements are specified in Division 3 Section Cast-in-Place Concrete. PART 2 PRODUCTS 2.01 BASE-MOUNTED PUMPS A. Acceptable Manufacturers 1. Armstrong 2. Bell and Gossett 3. Taco B. General Pump Requirements 1. Pump Units: Factory assembled and tested. 2. Motors: Include built-in, thermal-overload protection and grease-lubricated ball bearings. Select each motor to be non-overloading over full range of pump performance curve. If variable speed drives are used, provide inverter duty motors Page 2 of 6

3 3. Motors Indicated to Be Energy Efficient: minimum efficiency as indicated according to IEEE 112, Test Method B. Include motors with higher efficiency than "average standard industry motors" according to IEEE 112, Test Method B, if efficiency is not indicated. C. FLEXIBLE-COUPLED, END-SUCTION PUMPS 1. Description: base-mounted, centrifugal, flexible-coupled, end-suction, single-stage, bronze-fitted, back-pull-out, radially split case design; rated for 175-psig minimum working pressure and a continuous water temperature of 225 deg F. a) Casing: cast iron, with flanged piping connections, drain plug at low point of volute, threaded gage tappings at inlet and outlet connections, and integral feet or other means on volute to support weight of casing and attached piping. Casing shall allow removal and replacement of impeller without disconnecting piping. b) Impeller: ASTM B 584, cast bronze, statically and dynamically balanced, closed, overhung, single suction, keyed to shaft, and secured by locking cap screw. c) Wear Rings: replaceable, bronze casing ring. d) Shaft and Sleeve: steel shaft with bronze sleeve. e) Seals: mechanical, with carbon-steel rotating ring, stainless-steel spring, ceramic seat, and flexible bellows and gasket. f) Seals: stuffing box, with at least four rings of graphite-impregnated braided yarn with bronze lantern ring between center two graphite rings, and bronze packing gland. g) Coupling: flexible, capable of absorbing torsional vibration and shaft misalignment. h) Coupling Guard: steel, removable, and attached to mounting frame. i) Mounting Frame: welded-steel frame and cross members, factory fabricated from ASTM A 36/A 36M channels and angles. Fabricate for mounting pump casing, coupling guard, and motor. Field-drill motor-mounting holes for field-installed motors. j) Motor: secured to mounting frame, with adjustable alignment HORIZONTAL SPLIT-CASE PUMPS A. Acceptable Manufacturers 1. Aurora 2. Bell & Gossett 3. Taco 4. Armstrong B. Description: base-mounted, centrifugal, flexible-coupled, double-suction, single-stage, bronze-fitted, axially split case design; rated for 175-psig minimum working pressure and a continuous water temperature of 225 deg F, with mechanical seals and impeller mounted between bearings IN-LINE PUMPS A. Approved Manufacturers: 1. Armstrong 2. Bell and Gossett 3. Taco 4. Paco B. Description: Horizontal, in-line, centrifugal, single-stage, bronze-fitted, radially split case design; rated for 125-psig minimum working pressure and a continuous water temperature of 225 deg F PUMP SPECIALTY FITTINGS Page 3 of 6

4 A. Suction Diffuser: angle or straight pattern, 175-psig pressure rating, cast-iron body and end cap, pump-inlet fitting; with bronze startup and bronze or stainless-steel permanent strainers; bronze or stainless-steel straightening vanes; drain plug; and factory- or field-fabricated support. B. Triple-Duty Valve: angle or straight pattern, 175-psig pressure rating, cast-iron body, pump-discharge fitting; with drain plug and bronze-fitted shutoff, balancing, and check valve features STEAM CONDENSATE RETURN PUMPS/RECEIVERS (ELECTRIC) A. Approved Manufacturers: 1. Hoffman. ITT Fluid Handling; Div. of ITT Fluid Technology Corp. 2. Weil Pump Company, Inc. B. Description: factory-fabricated, packaged, electric-drive pump units; with receiver, pumps, controls, and accessories suitable for operation with low-pressure steam condensate. C. Configuration: floor-mounting, duplex unit with receiver and float switches. 1. Control Circuits: independent of each pump with electrical alternator to operate pumps in sequence and allow both pumps to operate on receiver high level. 2. Manual Lead-Lag Control: overrides electrical alternator when active pump is manually selected and allows both pumps to operate on receiver high level STEAM CONDENSATE RETURN PUMPS/RECEIVERS (STEAM OR AIR) A. Acceptable Manufacturers 1. Watson-McDaniel 2. Yarway 3. Armstrong B. Description: factory-fabricated, pressure-powered pump units with body and receivers constructed of cast iron or welded steel and with controls, valves, piping connections, and accessories suitable for pumping low. C. Configuration: packaged duplex unit with float-operated valve control and receiver. PART 3 EXECUTION 3.01 INSTALLATION OF PUMPS A. Install pumps to provide access for periodic maintenance, including removing motors, impellers, couplings, and accessories. B. Support pumps and piping separately so piping is not supported by pumps. C. Suspend in-line pumps using continuous-thread hanger rod and vibration-isolation hangers. Install seismic bracing as required by authorities having jurisdiction. D. Set base-mounted pumps on concrete foundation. Disconnect coupling halves before setting. Do not reconnect couplings until alignment operations have been completed. 1. Support pump baseplate on rectangular metal blocks and shims, or on metal wedges with small taper, at points near foundation bolts to provide a gap of 3/4 to 1-1/2 inches between pump base and foundation for grouting. 2. Adjust metal supports or wedges until pump and driver shafts are level. Check coupling faces and suction and discharge flanges of pump to verify that they are level and plumb. E. Automatic Condensate Pump Units: Install units for collecting condensate and extend to open drain ALIGNMENT A. Align pump and motor shafts and piping connections after setting them on foundations, after grout has been set and foundation bolts have been tightened, and after piping connections have been made Page 4 of 6

5 B. Comply with pump and coupling manufacturers' written instructions. C. After alignment is correct, tighten foundation bolts evenly but not too firmly. Completely fill baseplate with nonshrink, nonmetallic grout while metal blocks and shims or wedges are in place. After grout has cured, fully tighten foundation bolts CONNECTIONS A. Piping installation requirements are specified in other Division 15 Sections. Drawings indicate general arrangement of piping, fittings, and specialties. B. Install piping adjacent to machine to allow service and maintenance. C. Connect piping to pumps. Install valves that are the same size as piping connected to pumps. D. Install suction and discharge pipe sizes equal to or greater than diameter of pump nozzles. E. Install check valve and throttling valve on discharge side of in-line circulators. F. Install suction diffuser and shutoff valve on suction side of base-mounted pumps. G. Install triple-duty valve on discharge side of base-mounted pumps. H. Install flexible connectors on suction and discharge sides of base-mounted pumps between pump casing and valves. Flexible connectors shall not be used to correct for mis-alignment of piping. Provide a spool piece of pipe in place of the flexible connector to insure proper pipe alignment. Then remove spool and install the flexible connector. DPS Project Mangager shall inspect and approve the installation of flexible connectors. The contractor shall provide documentation that the pump is installed in accordance with the manufacturer s recommended tolerances. The flexible connection braiding shall not be used to compensate for offsets and alignment of the piping. The flexible connector shall not be compressed. I. Install pressure gauges on pump suction and discharge. Install at integral pressure-gauge tappings where provided. J. Install check valve and gate or ball valve on each condensate pump unit discharge. K. Install electrical connections for power, controls, and devices. L. Electrical power and control wiring and connections are specified in Division 16 Sections. M. Final close-out procedure: Remove start-up strainer and install permanent strainer. N. Final close-out procedure: Verify that the pump controls are correct for required application STEAM CONDENSATE PUMP INSTALLATION A. Install pumps according to manufacturer's written instructions. B. Install pumps to provide access for periodic maintenance, including removing motors, impellers, couplings, and accessories. C. Support pumps and piping separately so piping is not supported by pumps. D. Install pumps on concrete bases. Anchor pumps to bases using inserts or anchor bolts. E. Install thermometers and pressure gauges CONNECTIONS A. Drawings indicate general arrangement of piping, fittings, and specialties. Refer to Specification Section Hyrondic Piping and Specialties for additional requirements. B. Install piping adjacent to machine to allow service and maintenance. C. Install shutoff and check valves on inlet of pressure-operated units. D. Install inlet strainer and valved bypass to drain at system return connection. E. Install check valve, shutoff valve, and throttling valve at pump discharge connections for each pump unit Page 5 of 6

6 F. Install pipe drain to nearest floor drain for overflow and drain piping connections. G. Install full-size vent piping, terminating in 180 o elbow at point above highest steam system connection or as indicated. H. Install electrical connections for power, controls, and devices. I. Electrical power and control wiring and connections are specified in Division 16 Sections DEMONSTRATION A. Engage a factory-authorized service representative to train Owner's maintenance personnel to adjust, operate, and maintain pumps as specified below: 1. Train owner's maintenance personnel on procedures and schedules for starting and stopping, troubleshooting, servicing, and maintaining pumps. 2. Schedule training with owner, through architect, with at least seven days' advance notice. END OF SECTION Page 6 of 6