UFGS_23_52_00_Heating_Boilers_-_UFGS_23_52_00.pdf

SECTION 23 52 00 Page 1

SECTION 23 52 00

HEATING

BOILERS 04/08

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

AIR MOVEMENT AND CONTROL ASSOCIATION INTERNATIONAL (AMCA)

AMCA 801 (2001; R 2008) Industrial Process/Power

Generation Fans: Specification Guidelines

AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI)

ANSI Z21 .13/CSA 4.9 (2014; Errata 2014) Gas-Fired Low Pressure

Steam and Hot Water Boilers

AMERICAN SOCIETY OF HEATING, REFRIGERATING AND AIR-CONDITIONING

ENGINEERS (ASHRAE)

ASHRAE 52.2 (2012; Errata l 2013; INT l 2014; ADD A, B, AND D SUPP 2015; INT 3 2015; Errata 2 2015; ADD C 2015; ADD E, F 2016) Method of Testing General Ventilation Air-Cleaning Devices for Removal Efficiency by Particle Size

AMERICAN WATER WORKS ASSOCIATION (AWWA)

AWWA C606 (2015) Grooved and Shouldered Joints

AMERICAN WELDING SOCIETY (AWS)

AWS A5 .8/A5 .8M (2011; Amendment 2012) Specification for Filler Metals for Brazing and Braze Welding

AWS B2.2/B2.2M (2016) Specification for Brazing Procedure and Performance Qualification

ASME INTERNATIONAL (ASME)

ASME Bl.20.l (2013) Pipe Threads, General Purpose (Inch)

ASME Bl.20.2M (2006; R 2011) Pipe Threads, 60 Deg .

General Purpose (Metric)

ASME Bl6.ll (2011) Forged Fittings, Socket-Welding and

Threaded

SECTION 23 52 00 Page 2

ASME B16.15

ASME B16.18

ASME B16.20

ASME B16.22

ASME B16.26

ASME B16.3

ASME B16.34

ASME B16.39

ASME B16.4

ASME B16.5

ASME B16.9

ASME B31 .1

ASME B31 .5

ASME B40.100

ASME BPVC SEC IV

ASME BPVC SEC IX

ASME BPVC SEC VIII Dl

ASME CSD-1

ASME PTC 10

(2013) Cast Copper Alloy Threaded Fittings Classes 125 and 250

(2012) Cast Copper Alloy Solder Joint Pressure Fittings

(2012) Metallic Gaskets for Pipe Flanges - Ring-Joint, Spiral Wound, and Jacketed

(2013) Standard for Wrought Copper and Copper Alloy Solder Joint Pressure Fittings

(2013) Standard for Cast Copper Alloy Fittings for Flared Copper Tubes

(2011) Malleable Iron Threaded Fittings, Classes 150 and 300

(2013) Valves - Flanged, Threaded and Welding End

(2014) Standard for Malleable Iron Threaded Pipe Unions; Classes 150, 250, and 300

(2011) Standard for Gray Iron Threaded Fittings; Classes 125 and 250

(2013) Pipe Flanges and Flanged Fittings:

NPS 1/2 Through NPS 24 Metric/Inch Standard

(2012) Standard for Factory-Made Wrought Steel Buttwelding Fittings

(2016) Power Piping

(2016) Refrigeration Piping and Heat Transfer Components

(2013) Pressure Gauges and Gauge Attachments

(2010) BPVC Section IV-Rules for Construction of Heating Boilers

(2010) BPVC Section IX-Welding and Brazing Qualifications

(2010) BPVC Section VIII-Rules for Construction of Pressure Vessels Division 1

(2016) Control and Safety Devices for Automatically Fired Boilers

(1997; R 2014) Performance Test Code on Compressors and Exhausters

SECTION 23 52 00 Page 3

ASTM INTERNATIONAL (ASTM)

ASTM A105/A105M (2014) Standard Specification for Carbon

Steel Forgings for Piping Applications

ASTM A167 (2011) Standard Specification for

Stainless and Heat-Resisting Chromium-Nickel Steel Plate, Sheet, and Strip

ASTM A183 (2014) Standard Specification for Carbon

Steel Track Bolts and Nuts

ASTM A193/A193M (2016) Standard Specification for

Alloy-Steel and Stainless Steel Bolting Materials for High-Temperat ure Service and Other Special Purpose Applications

ASTM A234/A234M (2016) Standard Specification for Piping

Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service

ASTM A515/A515M (2010) Standard Specification for Pressure

Vessel Plates, Carbon Steel, for Intermediate- and Higher-Temperature Service

ASTM A516/A516M (2010; R 2015) Standard Specification for

Pressure Vessel Plates, Carbon Steel, for Moderate- and Lower-Temperature Service

ASTM A53/A53M (2012) Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless

ASTM A536 (1984; R 2014) Standard Specification for

Ductile Iron Castings

ASTM A653/A653M (2015; E 2016) Standard Specification for

Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process

ASTM B32 (2008; R 2014) Standard Specification for

Solder Metal

ASTM B62 (2015) Standard Specification for Composition

Bronze or Ounce Metal Castings

ASTM B75/B75M (2011) Standard Specification for Seamless

Copper Tube

ASTM B813 (2016) Standard Specification for Liquid and

Paste Fluxes for Soldering of Copper and Copper Alloy Tube

ASTM B828 (2016) Standard Practice for Making

Capillary Joints by Soldering of Copper

SECTION 23 52 00 Page 4 and Copper Alloy Tube and Fittings

ASTM B88 (2016) Standard Specification for Seamless

Copper Water Tube

ASTM B88M (2016) Standard Specification for Seamless

Copper Water Tube (Metric)

ASTM Cl55 (1997; R 2013) Standard Specification for

Insulating Firebrick

ASTM C27 (1998; R 2008) Fireclay and High-Alumina

Refractory Brick

ASTM C34 (2013) Structural Clay Load-Bearing Wall

Tile

ASTM C401 (2012) Alumina and Alumina-Silicate

Castable Refractories

ASTM Dl784 (2011) Standard Specification for Rigid

Poly(Vinyl Chloride) (PVC) Compounds and Chlorinated Poly(Vinyl Chloride) (CPVC) Compounds

ASTM D2000 (2012) Standard Classification System for

Rubber Products in Automotive Applications

ASTM D596 (2001; R 2011) Reporting Results of

Analysis of Water

ASTM Fl097 (1991; R 2012) Mortar, Re fractory

(High-Temperature, Air-Setting)

ASTM Fll39 (1988; R 2015) Steam Traps and Drains

ASTM F876 (2015a) Crosslinked Polyethylene (PEX)

Tubing

COMPRESSED AIR AND GAS INSTITUTE (CAGI)

CAGI Bl9 .l (2010) Safety Standard for Compressor

Systems

COPPER DEVELOPMENT ASSOCIATION (CDA)

CDA A4015 (2010) Copper Tube Handbook

EXPANSION JOINT MANUFACTURERS ASSOCIATION (EJMA)

EJMA Stds (2011) EJMA Standards

HYDRONICS INSTITUTE DIVISION OF AHRI (HYI)

HI-004 (1995) Radiant Floor Heating

HYI-005 (2008) I=B=R Ratings for Boilers, Baseboard Radiation and Finned Tube (Commercial)

MANUFACTURERS STANDARD IZATION SOCIETY OF THE VALVE AND FITTINGS

SECTION 23 52 00 Page 5

INDUSTRY (MSS)

MSS SP-110 (2010) Ball Valves Threaded, Socket-Welding, Solder Joint, Grooved and Flared Ends

MSS SP-25 (2013) Standard Marking System for Valves, Fittings, Flanges and Unions

MSS SP-58 (1993; Reaffirmed 2010) Pipe Hangers and

Supports - Materials, Design and Manufacture, Selection, Application, and Installation

MSS SP-70 (2011) Gray Iron Gate Valves, Flanged and

Threaded Ends

MSS SP-71 (2011; Errata 2013) Gray Iron Swing Check

Valves, Flanged and Threaded Ends

MSS SP-72 (2010a) Ball Valves with Flanged or

Butt-Welding Ends for General Service

MSS SP-78 (2011) Cast Iron Plug Valves, Flanged and

Threaded Ends

MSS SP-80 (2013) Bronze Gate, Globe, Angle and Check

Valves

MSS SP-85 (2011) Gray Iron Globe & Angle Valves

Flanged and Threaded Ends

NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)

NEMA 250 (2014) Enclosures for Electrical Equipment

(1000 Volts Maximum)

NEMA MG 1 (2016) Motors and Generators

NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)

NFPA 211 (2016) Standard for Chimneys, Fireplaces, Vents, and Solid Fuel-Burning Appliances

NFPA 31 (2016) Standard for the Installation of

Oil-Burning Equipment

NFPA 54 (2015) National Fuel Gas Code

NFPA 70 (2017) National Electrical Code

NFPA 85 (2015; Errata 1 2015) Boiler and

Combustion Systems Hazards Code

U .S . DEPARTMENT OF ENERGY (DOE)

Energy Star (1992; R 2006) Energy Star Energy

Efficiency Labeling System (FEMP)

UNDERWRITERS LABORATORIES (UL)

SECTION 23 52 00 Page 6

UL 1738 (2010; Reprint Nov 2014) Venting Systems for Gas-Burning Appliances, Categories II, III and IV

UL 296 (2003; Reprint Jun 2015) Oil Burners

UL 726 (1995; Reprint Oct 2013) Oil-Fired Boiler

Assemblies

UL 795 (2016) UL Standard for Safety Commercial-Industrial Gas Heating Equipment

UL FLAMMABLE & COMBUSTIBLE (2012) Flammable and Combustible Liquids and Gases Equipment Directory l.2 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. Submit the following in accordance with Section 01 33 00, SUBM ITTAL PROCEDURES:

SD-02 Shop Drawings Detail

Drawings

SD-03 Product Data Materials and Equipment Spare Parts

Water Treatment System

Boiler Water Treatment

Heating System Tests Fuel

System Tests

Unit Heaters Welding

Qualifications Field

Instructions Tests

SD-06 Test Reports Heating

System Tests Fuel

System Tests

Water Treatment Testing

SD-07 Certificates

Bolts

Continuous Emissions Monitoring Energy

Star

SECTION 23 52 00 Page 7

SD-10 Operation and Maintenance Data

Operation and Maintenance Instructions; G

Water Treatment System ; G

1.3 QUALITY ASSURANCE

Submit a copy of qualified welding procedures and a list of names and identification symbols of qualified welders and welding operators, at least 2 weeks prior to the start of welding operations. [Boilers and piping shall be welded and bra zed in accordance with qualified procedures using performance-qualified welders and welding operators. Procedures and welders shall be qualified in accordance with ASME BPVC SEC IX. Welding procedures qualified by others, and welders and welding operators qualified by another employer may be accepted as permitted by ASME B31 .1. Notify the Contracting Officer 24 hours in advance of tests, and the tests shall be performed at the work site if practical. The welder or welding operator shall apply the personally assigned symbol near each weld made as a permanent record.

1.4 DELIVERY, STORAGE, AND HANDLING

Protect equipment delivered and placed in storage from the weather, humidity and temperature variations, dirt and dust, and other contaminants.

1.5 EXTRA MATERIALS

Submit spare parts data for each different item of material and equipment specified, after approval of the detail drawings and no later than 2 months prior to the date of beneficial occupancy . Submit Detail Drawings consisting of equipment layout including installation details and electrical connection diagrams; combustion and safety control diagrams;

ductwork layout showing the location of supports and hangers, typical hanger details, gauge reinforcement, reinforcement spacing rigidity classification, and static pressure and seal classifications; and piping layout showing the location of guides and anchors, the load imposed on each support or anchor (not required for radiant floor tubing), and typical support details. Include on the drawings any information required to demonstrate that the system has been coordinated and will properly function as a unit and to show equipment relationship to other parts of the work, including clearances required for operation and maintenance . Include in the data a complete list of parts and supplies, with current unit prices and source of supply, and a list of the parts recommended by the manufacturer to be replaced after l and 3 years of service.

PART 2 PRODUCTS

2 .1 PRODUCT SUSTAINABILITY CRITERIA

For products in this section, where applicable and to extent allowed by performance criteria, provide and document the energy efficient equipment for boilers.

2 .2 MATERIALS AND EQUIPMENT

2 .2.1 Standard Products

SECTION 23 52 00 Page 8

Provide materials and equipment which are the standard products of a manufacturer regularly engaged in the manufacture of the products and that essentially duplicate items that have been in satisfactory use for at least 2 years prior to bid opening. Equipment shall be supported by a service organization that is, in the opinion of the Contracting Officer, reasonably convenient to the site. Submit manufacturer's catalog data included with the detail drawings for the following:

a. Radiant floor heating system including tubing, joints, and manifold for radiant floor heating systems.

b. Data showing model, size, options, etc ., that are intended for consideration. Data submitted shall be adequate to demonstrate compliance with contract requirements. Data shall include manufacturer's written installation instructions and manufacturer's recommendations for operation and maintenance clearances for the following:

(1) Boilers

(2) Unit Heaters

(3) Fuel Burning Equipment

(4) Combustion Control Equipment

(5) Pumps

(6) Fittings and Accessories

(7) Not Used.

(8) Water Treatment System

2 .2.2 Asbestos Prohibition

Asbestos and asbestos-containing products will not be allowed.

2 .2.3 Nameplates

Secure a plate to each major component of equipment containing the manufacturer's name, address, type or style, model or serial number, catalog number. Also, display an ENERGY STAR labels as applicable.

pressure vessel shall have an approved ASME stamp .

and Each

SECTION 23 52 00 Page 9

2 .2.4 Equipment Guards

Belts, pulleys, chains, gears, couplings, projecting setscrews, keys, and other rotating parts exposed to personnel contact shall be fully enclosed or guarded in accordance with OSHA requirements . High temperature equipment and piping exposed to contact by personnel or where it creates a potential fire hazard shall be properly guarded or covered with insulation of a type specified .

2 .3 BOILERS

Each boiler shall have the output capacity in British thermal units per hour (Btuh) as indicated when fired with the specified fuels. The boiler shall be furnished complete with the gas burning equipment, boiler fittings and trim , automatic controls, forced draft fan, natural draft/atmospheric burner, electrical wiring, insulation, piping connections, and protective jacket . The boiler shall be completely assembled and tested at the manufacturer's plant. Boiler auxiliaries including fans, motors, drives, and similar equipment shall be provided with at least 10 percent excess capacity to allow for field variations in settings and to compensate for any unforeseen increases in pressure losses in appurtenant piping and ductwork. However, the boiler safety devices shall not be sized for a 10 percent excess capacity. The boiler and its accessories shall be designed and installed to permit ready accessibility for operation, maintenance, and service. Boilers shall be designed, constructed, and equipped in accordance with ASME BPVC SEC IV .

Each boiler shall be of the condensing type and designed for water service as specified herein. The boiler capacity shall be based on the ratings shown in HYI-005 or as certified by the American Boiler Manufacturers Association, or American Gas Association.

2 .3.2 Condensing Boiler

Each boiler shall be a self-contained packaged type, complete with accessories, mounted on a structural steel base or a steel base which is integral to the boiler shell. Each boiler shall conform to the commercial design used by the manufacturer and shall permit free thermal expansion without placing undue stress on any part of the boiler . Each boiler which experiences the formation of condensate within the flue gas shall be specifically designed for condensing application . Each boiler shall withstand the corrosive effects of condensate for each part which may be in contact with the condensate at all possible operating conditions . Each boiler shall be provided with a separate air intake, exhaust, and condensate drain. Each boiler shall be designed to withstand the water temperature differentials anticipated at the required operating conditions without experiencing any damage due to thermal shock .

2 .3.3 Modular Configuration

Modular boilers shall be of the condensing type . Modular boilers shall have the capability of independent operation. Upon failure of any module, the remaining modules shall be capable of operating at their designed capacity .

2 .3.6 Hot Water Heating Boilers

The hot water heating boiler shall be capable of operating at the specified maximum continuous capacity without damage or deterioration to the boiler, its setting, firing equipment, or auxiliaries. The rated capacity shall be the capacity at which the boiler will operate continuously while

SECTION 23 52 00 Page 10 maintaining at least the specified minimum efficiency . The boiler design conditions shall be as noted on the design drawings.

2 .4 FUEL BURNING EQU IPMENT

Boiler shall be designed to burn gas. Each boiler shall comply with Federal, state, and local emission regulations.

2 .4.l Burners

2 .4.l.l Gas Fired Burners and Controls

Burners shall be UL approved mechanical draft burners with all air necessary for combustion supplied by a blower where the operation is coordinated with the burner. Burner shall be provided complete with fuel supply system in conformance with the following safety codes or standards:

a. Gas-fired units with inputs greater than 0.117 MW 400,000 Btuh per combustion chamber shall conform to UL 795. Gas fired units less than 3.66 MW 12,500,000 Btuh input shall conform to ANSI Z21.13/CSA 4.9.

b. Single and multiple burner gas-fired units greater than or equal to

3.66 MW 12,500,000 Btuh input shall conform to NFPA 85.

2 .4.2 Draft Fans

Fans conforming to AMCA 801 forced-draft shall be furnished as an integral part of boiler design. Fans shall be centrifugal with backward-curved blades or axial flow type. Each fan shall be sized for output volume and static pressure rating sufficient for pressure losses, excess air requirements at the burner, leakages, temperature, and elevation corrections for worst ambient conditions, all at full combustion to meet net-rated output at normal firing conditions, plus an overall excess air volume of 10 percent against a 20 percent static overpressure. Noise levels for fans shall not exceed 85 decibels in any octave band at a 0.914 m 3 foot station. Forced draft fan bearings shall be air cooled.

2 .4.2.1 Draft Fan Control

[Forced-draft centrifugal fans shall have inlet vane controls or shall have variable speed control where indicated. Inlet vanes shall be suitable for use with combustion control equipment. Axial propeller fans shall have variable propeller pitch control.

2 .4.2.2 Draft Fan Drives

Fans shall be driven by electric motors. Electric motor shall be totally enclosed fan cooled. [Motor starter shall be magnetic across-the-line type with watertight enclosure and shall be furnished with four auxiliary interlock contacts.

SECTION 23 52 00 Page 11

2 .4.3 Draft Damper

Boilers shall be provided with manual dampers, draft hoods, or barometric dampers as recommended by the boiler manufacturer to maintain proper draft in the boiler. Draft damper shall be provided in a convenient and accessible location in the flue gas outlet from the boiler.

2 .4.4 Ductwork

Air ducts connecting the forced-draft fan units with the plenum chamber shall be designed to convey air with a minimum of pressure loss due to friction. Ductwork shall be galvanized sheet metal conforming to ASTM A653/A653M. Ducts shall be straight and smooth on the inside with laps made in direction of air flow. Ducts shall have cross-break with enough center height to assure rigidity in the duct section, shall be angle iron braced, and shall be completely free of vibration. Access and inspection doors shall be provided as indicated and required, with a minimum of one in each section between dampers or items of equipment.

Ducts shall be constructed with long radius elbows having a centerline radius 1-1/2 times the duct width, or where the space does not permit the use of long radius elbows, short radius or square elbows with factory-fabricated turning vanes may be used . Duct joints shall be substantially airtight and shall have adequate strength for the service, with 38 x 38 x 3 mm 1-1/2 x 1-1/2 x 1/8 inch angles used where required for strength or rigidity. Duct wall thickness shall be 16 gauge (1.5 mm0.0598 inch) for ducts 1500 mm 60 inches or less and 12 gauge (2 .66 mm0 .1046 inch) for ducts larger than 1500 mm 60 inches in maximum dimension. Additional ductwork shall be in accordance with Section 23 00 00 AIR SUPPLY, DISTRIBUTION, VENTILATION, AND EXHAUST SYSTEM.

2 .5 COMBUSTION CONTROL EQUIPMENT

Combustion control equipment shall be provided as a system by a single manufacturer . Field installed automatic combustion control system shall be installed in accordance with the manufacturer's recommendations and under the direct supervision of a representative of the control manufacturer.

The boiler water temperature shall be controlled by a water temperature controller. The equipment shall operate electronically.

2 .5.l Omitted

2.5.2 Electrical controls

Electrical control devices shall be rated at 24 volts and shall be connected as specified in Section 26 20 00 INTERIOR DISTRIBUTION SYSTEM.

2 .5.3 Water Temperature Controller

The controller shall be of sturdy construction and shall be protected against dust and dampness. The thermostatic element shall be inserted in a separable socket installed in the upper part of the boiler near the water outlet. Modulating controllers shall control the fuel burning equipment to maintain set boiler water temperature within 2 percent. Controller shall be furnished with necessary equipment to automatically adjust the setting to suit the outside weather conditions. The outside air reset controller shall be operated in such a manner that the operating temperatures required by the boiler manufacturer are not compromised.

2 .5.4 Omitted

2 .5.5 Omitted

SECTION 23 52 00 Page 12

2 .5.6 Boiler Combustion Controls and Positioners

a. Gas boiler units shall be provided with modulating combustion controls with gas pilot or spark ignition . Modulating controls shall be provided with a means for manually controlling the firing rate.

b. Note used.

c. Modulating control function shall be accomplished using positioning type controls. Air flow ratio and fuel control valve shall be controlled by relative positions of operative levers on a jackshaft responding to a water temperature controller. Positioning type combustion control equipment shall include draft controls with synchronized fuel feed and combustion air supply controls, while and shall maintain the proper air/fuel ratio. The desired furnace draft shall be maintained within 0.25 mm 0.01 inch of water column.

2 .5.7 Combustion Safety Controls and Equipment

Combustion safety controls and equipment shall be UL listed, microprocessor-based distributed process controller. The system shall include mounting hardware, wiring and cables, and associated equipment.

The controller shall be mounted completely wired, programmed, debugged, and tested to perform all of its functions. The controller shall process the signals for complete control and monitoring of the boiler. This shall include maintaining boiler status, starting and stopping all control functions, sequencing control functions and signaling alarm conditions .

The program shall be documented and include cross references in description of coils and contacts . Microprocessor shall be able to per form self diagnostics and contain a message center to provide operator with status and failure mode information. Controllers for each boiler shall be mounted on a separate, free standing panel adjacent to the boiler or for packaged boilers on the boiler support ing structure . Control systems and safety devices for automatically fired boilers shall conform to ASME CSD-1.

Electrical combustion and safety controls shall be rated at 120 volts, single phase, 60 Hz and shall be connected as specified in Section 26 20 00 INTERIOR DISTRIBUTION SYSTEM . A 100 mm 4 inch diameter alarm bell shall be provided and shall be located where indicated or directed . The alarm bell shall ring when the boiler is shut down by any safety control or interlock . Indicating lights shall be provided on the control panel. A red light shall indicate flame failure, and a green light shall indicate that the main fuel valve is open. The following shutdown conditions shall require a manual reset be fore the boiler can automatically recycle :

a. Flame failure .

b . Failure to establish pilot flame .

c. Failure to establish main flame .

SECTION 23 52 00 Page 13

d. Low-water cutoff.

e . High temperature cutoff

2 .5.7.l Low-water Cutoff

Low water cutoff shall be float actuated switch or electrically actuated probe type low-water cutoff.

Float chamber shall be provided with a blow-down connection. Cutoff shall cause a safety shutdown and sound an alarm when the boiler water level drops below a safe minimum level.

A safety shutdown due to low water shall require manual reset before operation can be resumed and shall prevent recycling of the burner. The cutoff shall be in strict accordance to

ASME CSD-1.

2 .5.7.l.l Feedwater Regulator with Low-Water Cutoff

Regulator shall be an approved design sized for the application . A regulator shall be provided for each boiler. The feeder shall be so arranged that water will be fed to the boiler automatically when the water level in the boiler drops below a preset point and will actuate the alarm bell when the water level reaches the low danger point . The boiler feeder shall be arranged so that the burner and forced-draft fan will stop whenever the water level drops below a preset danger point . The boiler feeder shall be constructed so that the feedwater valve and seat are isolated from the float chamber to prevent overheating of the feed water and precipitation of scale on either the valve or seat . Each float mechanism, valve, and seat shall be constructed of an approved, durable, corrosion-resistant steel alloy . Valve seats shall be removable and renewable . The regulator shall be equipped with a large, self-cleaning strainer . The drain valve on the regulator shall be the gate or other straight-through type .

2 .5.7.1.2 Pump Controller with Low-Water Cutoff

Controller shall be a design approved by the boiler manufacturer. A pump controller shall be provided for each boiler which is used for space heating and process steam loads or long distribution lines . Pump controller shall control the operation of the burner, forced-draft fan, and pump . Pump controller and low-water cutoff shall have a float-operated mercury switch arranged to start and stop the pump at preset boiler water levels. If the water level in the boiler reaches the low danger point, a second mercury switch shall shut down the burner and actuate the alarm bell.

2 .5.7.1.3 Supplementary Low-Water Cutoff

Supplementary low-water cutoff of the electrically operated probe type shall be provided in addition to the low-water cutoff required above on each boiler. Supplementary low-water cutoff shall be mounted directly in the boiler shell and shall be set below the low-water cutoff required above .

2 .5.7.2 Water Flow Interlock

Hot water boiler limit controls shall be provided to include protection for low boiler water flow and high boiler water temperature . The limit controls shall be interlocked with the combustion control system to effect boiler alarm and shutdown . The controls shall not allow boiler startup unless hot water flow is proven.

SECTION 23 52 00 Page 14

2 .6 PUMPS

2 .6.l Omitted

2 .6.2 Hot Water and Boiler Circulating Pumps

Circulating pumps for hot water shall be electrically driven single-stage centrifugal type and have a capacity not less than indicated . Boiler circulating pumps shall be supported by the piping on which installed and shall be flexible-coupled shaft. The boiler circulating pumps shall be vertical split case type.

The motor shall have sufficient power for the service required, shall be of a type approved by the manufacturer of the pump, shall be suitable for the available electric service, and shall conform to the requirements of paragraph ELECTRICAL EQUIPMENT.

Each pump suction and discharge connection shall be provided with a pressure gauge as specified. The boiler circulating pump discharge heater shall be provided with a flow switch.

Flow switch unit shall be a self-contained swinging vane type to indicate fluid flow. Switch shall be a SPOT with 120-volt, 15-ampere rating .

2 .6.3 Omitted

2 .6.4 Omitted

2 .7 COLD WATER CONNECTIONS

Connections shall be provided which includes consecutively in line a strainer, reduced pressure principle backflow preventers, and water pressure regulator in that order in the direction of the flow . The reduced pressure principle back flow preventers shall be provided as indicated and in compliance with Section 22 00 00 PLUMBING, GENERAL PURPOSE. Cold water fill connections shall be made to the water supply system as indicated.

Necessary pipe, fittings, and valves required for water connections between the boiler and cold water main shall be provided as shown. The pressure regulating valve shall be of a type that will not stick or allow pressure to build up on the low side . The valve shall be set to maintain a terminal pressure of approximately 35 kPa 5 psi in excess of the static head on the system and shall operate within a 15 kPa 2 psi tolerance regardless of cold water supply piping pressure and without objectionable noise under any condition of operation.

2 .8 OMITTED

2 .9 OMITTED

2.10 OMITTED

2 .11 OMITTED

2 .12 OMITTED

2 .13 FITTINGS AND ACCESSORIES

Boiler fittings and accessories shall be installed with each boiler in

SECTION 23 52 00 Page 15 accordance with ASME BPVC SEC IV, unless otherwise specified.

2 .13.1 Direct Vents

Direct venting shall be used for condensing type boilers. Both the air intake and exhaust vents shall be sized and located as indicated on the drawings and as recommended by the boiler manufacturer. A separate combustion air intake vent and exhaust vent shall be provided for each boiler .

2 .13.1.1 Combustion Air Intake Vent

The combustion air intake piping shall be constructed of Schedule 40 PVC in accordance with ASTM D1784. The vent shall be suitable for the temperature at the boiler combustion air intake connection point . Each intake shall be provided complete with bird screen.

2 .13.1.2 Exhaust Vent

The exhaust vent piping shall be constructed of Schedule 40 CPVC or stainless steel conforming to UL 1738 and the boiler manufacturer 's recommendations. Plastic materials polyetherimide (PEI) and polyethersulfone (PES) are forbidden to be used for vent piping of combustion gases . The exhaust vent shall be suitable for the maximum anticipated boiler exhaust temperature and shall withstand the corrosive effects of the condensate . A 8 mm 0.3125 inch diameter hole shall be provided in the stack not greater than 152 mm 6 inches from the boiler flue outlet for sampling of the exit gases . A method shall be provided to seal the hole to prevent exhaust gases from entering the boiler room when samples are not being taken . Each exhaust stack shall be provided complete with bird screen.

2 .13.2 Expansion Tank

The hot water pressurization system shall include a diaphragm-type expansion tank which will accommodate the expanded water of the system generated within the normal operating temperature range, limiting the pressure increase at all components in the system to the maximum allowable pressure at those components . The only air in the system shall be the permanent sealed-in air cushion contained in the diaphragm-type tank. The sizes shall be as indicated . The expansion tank shall be welded steel, constructed, tested, and stamped in accordance with ASME BPVC SEC VIII Dl for a working pressure of 125 psi and precharged to the minimum operating pressure . The tank's air chamber shall be fitted with an air charging valve and pressure gauge . The tank shall be supported by steel legs or bases for vertical installation or steel saddles for horizontal installations . The tank shall have lifting rings and a drain connection. All components shall be suitable for a maximum operating temperature of 120 degrees C 250 degrees F.

2 .13.7 Air Separator

External air separation tank shall be steel, constructed, tested and stamped in accordance with ASME BPVC SEC VIII Dl for a working pressure of 125 psi. The capacity of the air separation tank indicated is minimum

2 .13.8 Filters

Filters shall conform to ASHRAE 52 .2.

2 .13.9 Foundation (Setting) Materials

SECTION 23 52 00 Page 16

2 .13.9.l Firebrick

Firebrick shall be ASTM C27 class as recommended by boiler manufacturer.

2 .13.9.2 Tile

Tile shall be ASTM C34, Grade LBX .

2 .13.9.3 Insulating Brick

Insulating brick shall comply with ASTM Cl55.

2 .13.9.4 Re fractory Mortar

Re fractory mortar shall comply with ASTM Fl097.

2 .13.9.5 Castable Refractories

Castable refractories shall be ASTM C401. The minimum modulus of rupture for transverse strength shall be not less than 4136 kPa 600 psi after being heat soaked for 5 hours or more at a temperature in excess of 2500 degrees F.

2 .13.10 Steel Sheets

2 .13.10.l Galvanized

Steel

Galvanized steel shall be ASTM A653/A653M.

2 .13.10.2 Uncoated Steel

Uncoated steel shall be composition, condition, and finish best suited to the intended use .

2 .13.11 Gaskets

Gaskets shall be nonasbestos material in accordance with ASME B16.20, full face or self-centering type . The gaskets shall be of the spiral wound type with graphite filler material.

2 .13.12 Steel Pipe and

Fittings 2 .13.12.1

Steel Pipe

Steel pipe shall be ASTM A53/A53M , Type E or S, Grade A or B, black steel, standard weight .

2 .13.12.2 Steel Pipe Fittings

Fittings shall have the manufacturer's trademark affixed in accordance with MSS SP-25 so as to permanently identify the manufacturer .

2 .13.12.3 Steel Flanges

Flanged fittings including flanges, bolts, nuts, bolt patterns, etc . shall be in accordance with ASME B16.5 class 150 and shall have the manufacturer's trademark affixed in accordance with MSS SP-25. Flange

SECTION 23 52 00 Page 17 material shall conform to ASTM A105/A105M . Flanges for high temperature water systems shall be serrated or raised-face type . Blind flange material shall conform to ASTM A516/A51 6M cold service and ASTM A515/A515M for hot service . Bolts shall be high strength or intermediate strength with material conforming to ASTM A193/A193M . Submit written certification by the bolt manufacturer that the bolts furnished comply with the requirements of this specification . The certification shall include illustrations of product markings, the date of manufacture, and the number of each type of bolt to be furnished based on this certification .

2 .13.12.4 Welded Fittings

Welded fittings shall conform to ASTM A234/A23 4M with WPA marking .

Buttwelded fittings shall conform to ASME B16.9, and socket-welded fittings shall conform to ASME B16.11.

2 .13.12.5 Cast-Iron Fittings

Fittings shall be ASME B16.4, Class 125, type required to match connecting piping.

2 .13.12.6 Malleable-Iron Fittings

Fittings shall be ASME B16.3, type as required to match connecting piping .

2 .13.12.7 Unions

Unions shall be ASME B16.39, Class 150.

2 .13.12.8 Threads

Pipe threads shall conform to ASME Bl .20.2MASME Bl .20.1.

2 .13.12.9 Grooved Mechanical fittings

Joints and fittings shall be designed for not less than 125 psig service and shall be the product of the same manufacturer . Fitting and coupling houses shall be ductile iron conforming to ASTM A536. Gaskets shall be molded synthetic rubber with central cavity, pressure responsive configuration and shall conform to ASTM 02000 for circulating medium up to 110 degrees C 230 degrees F. Grooved joints shall conform to AWWA C606.

Coupling nuts and bolts shall be steel and shall conform to ASTM A183.

2 .13.13 Copper Tubing and Fittings

2 .13.13.1 Copper Tubing

Tubing shall be ASTM B88M ASTM B88, Type K or L. Adapters for copper tubing shall be brass or bronze for brazed fittings.

2 .13.13.2 Solder-Joint Pressure Fittings

Wrought copper and bronze solder-joint pressure fittings shall conform to ASME B16.22 and ASTM B75/B75M . Cast copper alloy solder-joint pressure fittings shall conform to ASME B16.18 and ASTM B828.

2 .13.13.3 Flared Fittings

Cast copper alloy fittings for flared copper tube shall conform to ASME B16.26 and ASTM B62 .

SECTION 23 52 00 Page 18

2 .13.13.4 Adapters

Adapters may be used for connecting tubing to flanges and to threaded ends of valves and equipment . Extracted brazed tee joints produced with an acceptable tool and installed as recommended by the manufacturer may be used .

2 .13.13.5 Threaded Fittings

Cast bronze threaded fittings shall conform to ASME B16.15.

2 .13.13.6 Brazing Material

Brazing material shall conform to AWS A5 .8/A5 .8M .

2 .13.13.7 Brazing Flux

Flux shall be in paste or liquid form appropriate for use with brazing material. Flux shall be as follows: lead-free; have a 100 percent flushable residue; contain slightly acidic reagents; contain potassium borides, and contain fluorides . Silver brazing materials shall be in accordance with AWS A5 .8/A5 .8M .

2 .13.13.8 Solder Material

Solder metal shall conform to ASTM B32 95-5 tin-antimony.

2 .13.13.9 Solder Flux

Flux shall be either liquid or paste form, non-corrosive and conform to

ASTM B813.

2 .13.13.10 Grooved Mechanical Fittings

Joints and fittings shall be designed for not less than 125 psig service and shall be the product of the same manufacturer . Fitting and coupling houses shall be ductile iron conforming to ASTM A536. Gaskets shall be molded synthetic rubber with central cavity, pressure responsible configuration and shall conform to ASTM D2000, for circulating medium up to 110 degrees C 230 degrees F. Grooved joints shall conform to AWWA C606.

Coupling nuts and bolts shall be steel and shall conform to ASTM A183.

2 .13.14 Dielectric Waterways and Flanges

Dielectric waterways shall have temperature and pressure rating equal to or greater than that specified for the connecting piping . Waterways shall have metal connections on both ends suited to match connecting piping .

Dielectric waterways shall be internally lined with an insulator specifically designed to prevent current flow between dissimilar metals.

Dielectric flanges shall meet the performance requirements described herein for dielectric waterways .

2 .13.15 Flexible Pipe Connectors

Flexible pipe connectors shall be designed for 125 psi service .

Connectors shall be installed where indicated . The flexible section shall be constructed of rubber, tetrafluoroethylene resin, or corrosion-resisting steel, bronze, monel, or galvanized steel. Materials used and the configuration shall be suitable for the pressure, vacuum, and temperature medium . The flexible section shall be suitable for service intended and may have threaded, welded, soldered, flanged, or socket ends.

SECTION 23 52 00 Page 19

Flanged assemblies shall be equipped with limit bolts to restrict maximum travel to the manufacturer's standard limits . Unless otherwise indicated, the length of the flexible connectors shall be as recommended by the manufacturer for the service intended . Internal sleeves or liners, compatible with circulating medium, shall be provided when recommended by the manufacturer . Covers to protect the bellows shall be provided where indicated .

2 .13.16 Pipe Supports

Pipe supports shall conform to MSS SP-58.

2 .13.17 Pipe Expansion

2 .13.17.1 Expansion Loops

Expansion loops and offsets shall provide adequate expansion of the main straight runs of the system within the stress limits specified in ASME B31 .1. The loops and offsets shall be cold-sprung and installed where indicated.

Pipe guides and anchors shall be provided as indicated.

2 .13.18 Valves

Valves shall be Class 125 and shall be suitable for the application .

Grooved ends in accordance with AWWA C606 may be used for water service only . Valves in non-boiler external piping shall meet the material, fabrication and operating requirements of ASME B31 .1. The connection type of all valves shall match the same type of connection required for the piping on which installed .

2 .13.18.1 Gate Valves

Gate valves 65 mm 2-1/2 inches and smaller shall conform to MSS SP-80 bronze rising stem, threaded, solder, or flanged ends. Gate valves 80 mm 3 inches and larger shall conform to MSS SP-70 cast iron bronze trim, outside screw and yoke, flanged, or threaded ends.

2 .13.18.2 Globe Valves

Globe valves 65 mm 2-1/2 inches and smaller shall conform to MSS SP-80, bronze, threaded, soldered, or flanged ends. Globe valves 80 mm 3 inches and larger shall conform to MSS SP-85, cast iron, bronze trim , flanged, or threaded ends.

2 .13.18.3 Check Valves

Check valves 65 mm 2-1/2 inches and smaller shall conform to MSS SP-80, bronze, threaded, soldered, or flanged ends. Check valves 80 mm 3 inches and larger shall conform to MSS SP-71, cast iron, bronze trim , flanged, or threaded ends.

2 .13.18.4 Angle Valves

Angle valves 65 mm 2-1/2 inches and smaller shall conform to MSS SP-80 bronze, threaded, soldered, or flanged ends. Angle valves 80 mm 3 inches and larger shall conform to MSS SP-85, cast iron, bronze trim , flanged, or threaded ends.

SECTION 23 52 00 Page 20

2 .13.18.5 Ball Valves

Ball valves 15 mm 1/2 inch and larger shall conform to MSS SP-72 or MSS SP-110, ductile iron or bronze, threaded, soldered, or flanged ends.

2 .13.18.6 Plug Valves

Plug valves 51 mm 2 inch and larger shall conform to MSS SP-78. Plug valves smaller than 51 mm 2 inch shall conform to ASME B16.34.

2 .13.18.7 Grooved End Valves

Valves with grooved ends in accordance with AWWA C606 may be used if the valve manufacturer certifies that their performance meets the requirements of the standards indicated for each type of valve .

2 .13.18.8 Balancing Valves

Balancing valves shall have meter connections with positive shutoff valves. An integral pointer shall register the degree of valve opening.

Valves shall be calibrated so that flow rate can be determined when valve opening in degrees and pressure differential across valve is known. Each balancing valve shall be constructed with internal seals to prevent leakage and shall be supplied with preformed insulation. Valves shall be suitable for 120 degrees C 250 degrees F temperature and working pressure of the pipe in which installed . Valve bodies shall be provided with tapped openings and pipe extensions with shutoff valves outside of pipe insulation. The pipe extensions shall be provided with quick connecting hose fittings for a portable meter to measure the pressure differential.

One portable differential meter shall be furnished. The meter suitable for the operating pressure specified shall be complete with hoses, vent, and shutoff valves, and carrying cas . In lieu of the balancing valve with integral metering connections, a ball valve or plug valve with a separately installed orifice plate or venturi tube may be used for balancing.

2 .13.18.9 Automatic Flow Control Valves

In lieu of the specified balancing valves, automatic flow control valves may be provided to maintain constant flow and shall be designed to be sensitive to pressure differential across the valve to provide the required opening . Valves shall be selected for the flow required and provided with a permanent nameplate or tag carrying a permanent record of the factory-determined flow rate and flow control pressure levels. Valves shall control the flow within 5 percent of the tag rating . Valves shall be suitable for the maximum operating pressure of 850 kPa 125 psi or 150 percent of the system operating pressure, whichever is greater . Where the available system pressure is not adequate to provide the minimum pressure differential that still allows flow control, the system pump head capability shall be increased . Valves shall be suitable for 120 degrees C 250 degrees F temperature service . Valve materials shall be same as specified for the heating system check, globe, angle, and gate valves .

Valve operator shall be the electric motor type[ or pneumatic type as applicable]. Valve operator shall be capable of positive shutoff against the system pump head. Valve bodies shall be provided with tapped openings and pipe extensions with shutoff valves outside of pipe insulation. The pipe extensions shall be provided with quick connecting hose fittings for a

SECTION 23 52 00 Page 21 portable meter to measure the pressure differential across the automatic flow control valve . A portable meter shall be provided with accessory kit as recommended for the project by the automatic valve manufacturer.

2 .13.18.10 Butterfly Valves

Butterfly valves shall be 2-flange type or lug wafer type, and shall be bubble tight at 1135 kPa 150 psig . Valve bodies shall be cast iron, malleable iron, or steel. ASTM Al 67, Type 404 or Type 316, corrosion resisting steel stems, bronze, or corrosion resisting steel discs, and synthetic rubber seats shall be provided . Valves smaller than 200 mm 8 inches shall have throttling handles with a minimum of seven locking positions . Valves 200 mm 8 inches and larger shall have totally enclosed manual gear operators with adjustable balance return stops and position indicators. Valves in insulated lines shall have extended neck to accommodate insulation thickness .

2 .13.18.11 Drain valves

Drain valves shall be provided at each drain point of blowdown as recommended by the boiler manufacturer . Piping shall conform to ASME BPVC SEC IV and ASTM A53/A53M .

2 .13.18.12 Safety Valves

Safety valves shall have steel bodies and shall be equipped with corrosion-resistant trim and valve seats . The valves shall be properly guided and shall be positive closing so that no leakage can occur .

Adjustment of the desired back-pressure shall cover the range between 15 and 70 kPa 2 and 10 psig . The adjustment shall be made externally, and any shafts extending through the valve body shall be provided with adjustable stuffing boxes having renewable packing . Boiler safety valves of proper size and of the required number, in accordance with ASME BPVC SEC IV, shall be installed so that the discharge will be through piping extended

2 .13.19 Strainers

Basket and "Y" type strainers shall be the same size as the pipelines in which they are installed. The strainer bodies shall be heavy and durable, fabricated of cast iron, and shall have bottoms drilled and tapped with a gate valve attached for blowdown purposes. Strainers shall be designed for 1 2 5 psig service and 180 degrees F. The bodies shall have arrows clearly cast on the sides indicating the direction of flow.

Each strainer shall be equipped with an easily removable cover and sediment screen. The screen shall be made of 0.795 mm 22 gauge thick brass sheet or corrosion-resistant steel with small perforations numbering not less than 6,150/square m 400/square inch to provide a net free area through the basket of at least 3.30 times that of the entering pipe . The flow shall be into the screen and out through the perforations.

2 .13.20 Pressure Gauges

Gauges shall conform to ASME B40.100 and shall be provided with throttling type needle valve or a pulsation dampener and shutoff valve. Minimum dial

SECTION 23 52 00 Page 22 size shall be 90 mm 3-1/2 inches . A pressure gauge shall be provided for each boiler in a visible location on the boiler. Pressure gauges shall be provided with readings in psi. Pressure gauges shall have an indicating pressure range that is related to the operating pressure of the fluid in accordance with the following table:

Operating Pressure (psi) Pressure Range (psi)

76-150 0-200

16-75 0-100

2-15 0-30 (retard )

2 .13.21 Thermometers

Thermometers shall be provided with wells and separable corrosion-resistant steel sockets . Mercury shall not be used in thermometers. Thermometers the feedwater for each steam boiler shall be provided in a visible location on the boiler . Thermometers shall have brass, malleable iron, or aluminum alloy case and frame, clear protective face, permanent ly stabilized glass tube with indicating-fluid column, white face, black numbers, and a minimum 225 mm 9 inch scale . The operating range of the thermometers shall be 0- 100 degrees C 32-212 degrees F. The thermometers shall be provided with readings in degrees C F.

2 .13.22 Air Vents

2 .13.22 .l Manual Air Vents

Manual air vents shall be brass or bronze valves or cocks suitable for the pressure rating of the piping system and furnished with threaded plugs or caps.

2 .13.22 .2 Automatic Air Vents

Automatic air vents shall be 19 mm 3/4 inch quick-venting float and vacuum air valves . Each air vent valve shall have a large port permitting the expulsion of the air without developing excessive back pressure, a noncollapsible metal float which will close the valve and prevent the loss of water from the system, an air seal that will effectively close and prevent the re-entry of air into the system when subatmospheric pressures prevail therein, and a thermostatic member that will close the port against the passage of steam from the system . The name of the manufacturer shall be clearly stamped on the outside of each valve . The air vent valve shall be suitable for the pressure rating of the piping system .

2 .14 ELECTRICAL EQUIPMENT

Electric motor-driven equipment shall be provided complete with motors, motor starters, and necessary control devices. Electrical equipment, motor control devices, motor efficiencies and wiring shall be as specified in Section 26 20 00 INTERIOR DISTRIBUTION SYSTEM . Motors which are not an integral part of a packaged boiler and which are integral in size shall be the premium efficiency type in accordance with NEMA MG 1. Motors which are an integral part of the packaged boiler shall be the highest efficiency available by the manufacturer of the packaged boiler . Motor starters shall be provided complete with properly sized thermal overload protections and other appurtenances necessary for the motor control specified . Starters

SECTION 23 52 00 Page 23 shall be furnished in watertight enclosures . Manual or automatic control and protective or signal devices required for the operation specified and any control wiring required for controls and devices but not shown shall be provided.

2 .14.l Motor Ratings

Motors shall be suitable for the voltage and frequency provided. Motors 1/2 hp and larger shall be three-phase, unless otherwise indicated. Motors shall be of sufficient capacity to drive the equipment at the specified capacity without exceeding the nameplate rating on the motor.

2 .14.2 Motor Controls

Motor controllers shall be provided complete with properly sized thermal overload protection . Manual or automatic control and protective or signal devices required for the operation specified and any wiring required to such devices shall be provided .