USACE / NAVFAC / AFCESA / NASA UFGS-23 69 00.00 20 (July 2006)
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Preparing Activity: NAVFAC Superseding
UFGS-23 69 00.00 20 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 23 69 00.00 20
REFRIGERATION EQUIPMENT FOR COLD STORAGE
07/06
NOTE: This guide specification covers the requirements for requirements for
refrigeration equipment for cold storage facilities.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
NOTE: The following information shall be shown on the projects drawings:
1. Design refrigeration systems for cold storage using energy efficiency in
compliance with
FEMP/Energy Star requirements specified at www.eren.doe.gov/femp/procurement. Indicate
efficiency design parameters for equipment on the drawings.
PART 1 GENERAL
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
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-CONDITIONING, HEATING AND REFRIGERATION INSTITUTE (AHRI)AHRI 210/240(2006) Performance Rating of Unitary Air-Conditioning and Air-Source Heat Pump EquipmentAHRI 270(1995) Standard for Sound Rating of Outdoor Unitary EquipmentAHRI 420(2000) Unit Coolers for RefrigerationAHRI 450(2007) Standard for Water-Cooled Refrigerant Condensers, Remote TypeAHRI 460(2005) Performance Rating of Remote Mechanical-Draft Air-Cooled Refrigerant CondensersAHRI 495(2005) Performance Rating of Refrigerant Liquid ReceiversAHRI 520(2004) Performance Rating of Positive Displacement Condensing Units][AMERICAN INSTITUTE OF STEEL CONSTRUCTION (AISC)AISC 360(2005) Specification for Structural Steel Buildings, with Commentary][AMERICAN IRON AND STEEL INSTITUTE (AISI)AISI SG03-3(2002) Cold-Formed Steel Design Manual Set][AMERICAN SOCIETY OF HEATING, REFRIGERATING AND AIR-CONDITIONING ENGINEERS (ASHRAE)ASHRAE 15 & 34WARNING: Text in tags exceeds the maximum length of 300 charactersASHRAE 23(2005) Methods of Testing for Rating Positive Displacement Refrigerant Compressors and Condensing UnitsASHRAE 90.1 - IP(2007) Energy Standard for Buildings Except Low-Rise Residential Buildings, I-P EditionASHRAE 90.1 - SI(2004; Addendas a through p, r through v, x,ak 2006; Supp to Addendas 2006; Errata 2007; Interpretations 8 - 15:2007; Errata 2008; INT 16-21 2008; Errata 2008; INT 22-26 2008) Energy Standard for Buildings Except Low-Rise Residential Buildings, SI Edition][ASME INTERNATIONAL (ASME)ASME BPVC SEC VIII D1(2007; Addenda 2008) Boiler and Pressure Vessel Code; Section VIII, Pressure Vessels Division 1 - Basic Coverage][ASTM INTERNATIONAL (ASTM)ASTM A 123/A 123M(2008) Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel ProductsASTM A 153/A 153M(2005) Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel HardwareASTM A 653/A 653M(2008) Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip ProcessASTM B 117(2007a) Standing Practice for Operating Salt Spray (Fog) ApparatusASTM D 2996(2001; R 2007e1) Filament-Wound "Fiberglass" (Glass-Fiber-Reinforced Thermosetting-Resin) PipeASTM D 5864(2005) Standard Test Method for Determining Aerobic Aquatic Biodegradation of Lubricants or Their ComponentsASTM D 6081(1998; R 2004) Aquatic Toxicity Testing of Lubricants: Sample Preparation and Results InterpretationASTM E 2129(2005) Standard Practice for Data Collection for Sustainability Assessment of Building ProductsASTM E 84(2008a) Standard Test Method for Surface Burning Characteristics of Building Materials][COOLING TECHNOLOGY INSTITUTE (CTI)CTI ATC-105(2000) Acceptance Test Code][NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)NEMA ICS 1(2000; R 2005; R 2008) Standard for Industrial Control and Systems General RequirementsNEMA ICS 2(2000; Errata 2002; R 2005; Errata 2006) Standard for Industrial Control and Systems: Controllers, Contractors, and Overload Relays Rated Not More than 2000 Volts AC or 750 Volts DC: Part 8 - Disconnect Devices for Use in Industrial Control EquipmentNEMA ICS 3(2005) Standard for Industrial Control and Systems: Medium Voltage Controllers Rated 2001 to 7200 Volts ACNEMA ICS 4(2005) Industrial Control and Systems: Terminal BlocksNEMA ICS 6(1993; R 2006) Standard for Industrial Controls and Systems EnclosuresNEMA MG 1(2007; Errata 2008) Standard for Motors and Generators][NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)NFPA 70(2007; AMD 1 2008) National Electrical Code - 2008 Edition][U.S. ARMY CORPS OF ENGINEERS (USACE)EM 1110-2-1424(1999; Change 1) Lubricants and Hydraulic Fluids][U.S. GENERAL SERVICES ADMINISTRATION (GSA)CID A-A-59223(Basic; Notice 1) Cooling Towers, Liquid][UNDERWRITERS LABORATORIES (UL)UL 207(2001; Rev thru Nov 2004) Standard for Refrigerant-Containing Components and Accessories, Nonelectrical]1.2 SUBMITTALS
NOTE: Submittals must be limited to those necessary for adequate quality control.
The importance of an item in the project should be one of the primary factors
in determining if a submittal for the item should be required.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy projects.
Submittal items not designated with a "G" are considered as being for information
only for Army projects and for Contractor Quality Control approval for Navy
projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are [for Contractor Quality Control approval.][for information only. When used, a designation following the
"G" designation identifies the office that will review the submittal for the Government.] The following shall
be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Refrigeration equipment; G
Atmospheric cooling equipment, including supporting members; G
SD-03 Product Data
Unit coolers; G
[Compressor] [Condensing] units; G
Condensers; G
Atmospheric cooling equipment; G
Water treatment system; G
Automatic controls; G
Heat recovery devices; G
Motors; G
[Local/Regional Materials
Submit documentation indicating distance between manufacturing facility and the project site.
Indicate distance of raw material origin from the project site. Indicate relative dollar value
of local/regional materials to total dollar value of products included in project.]
[Environmental Data]
SD-06 Test Reports
Pressure vessels; G
Aquatic toxicity
SD-08 Manufacturer's Instructions
Refrigeration equipment; G
Water treatment system; G
Include instruction for evacuation and charging procedures and equipment start-up and initial
operation.
SD-10 Operation and Maintenance Data
Refrigeration equipment, Data Package 3; G
Automatic controls, Data Package 3; G
Motors, Data Package 3; G
Motor starters, Data Package 3; G
Water treatment system, Data Package 3; G
Submit in accordance with Section 01 78 23 OPERATION AND MAINTENANCE DATA.
1.3 QUALITY ASSURANCE
1.3.1 Modifications of References
Accomplish work in accordance with the referenced publications, except as modified by this section. Consider
the advisory or recommended provisions to be mandatory, as though the word "shall" had been substituted for the
words "should" or "could" or "may," wherever they appear. Interpret reference to "the Authority having jurisdiction,"
"the Administrative Authority," "the Owner," or "the Design Engineer" to mean the Contracting Officer.
1.3.2 Safety
Design, manufacture, and installation of refrigeration equipment shall conform to ASHRAE 15 & 34, UL 207,
and NFPA 70. Provide personnel protection from moving parts including fans, pulleys chains gears and couplings.
Guard or cover with insulation high temperature machinery and piping.
1.3.3 Pressure Vessels
The design, fabrication, inspection, and testing of pressure vessels including the waterside and refrigerant
side of condensers and evaporators shall be in accordance with ASME BPVC SEC VIII D1, and ASHRAE 15 & 34.
The presence of the ASME official Code U-Symbol or Code UM-Symbol stamped or marked on the vessels, and the submitting
of the applicable ASME required manufacturer's data report will be accepted as evidence that the pressure vessels
comply to the ASME rules for construction. Where referenced publications do not apply, pressure components shall
be tested at 1-1/2 times design working pressure. Refrigerant wetted carbon steel surfaces shall be pickled
or abrasive blasted free of mill scale, cleaned, dried, charged, and sealed. [Where service temperatures below
minus 7 degrees C 20 degrees F are encountered, materials of construction shall be low temperature alloy carbon
steel.] Nozzle length shall be approximately 1/3 greater than insulation thickness. Insulated vessels shall
be fitted with rings and other insulation supports as required for installation of insulation. Exterior surfaces
of vessels which are insulated and vapor barrier sealed shall be abrasive blasted and primed with 0.076 mm 3
mil dry film thickness of inorganic zinc rich coating.
1.3.4 Refrigeration Equipment
Include layout drawings and control diagrams of the refrigeration equipment.
1.4 REFRIGERATION PIPING AND ACCESSORIES
NOTE: Insert appropriate Section number and title in blank below using format
per UFC 1-300-02.
Provide as specified under [_____].
1.5 ENVIRONMENTAL REQUIREMENTS
Assess potential effects of all lubricants on aquatic organisms in accordance with ASTM D 6081 and submit aquatic
toxicity reports. Assess biodegradation in accordance with ASTM D 5864. In accordance with EM 1110-2-1424 Chapter
8, aquatic toxicity shall exceed 1,000 ppm at LL50 and biodegradation shall exceed 60 percent conversion of carbon
to carbon dioxide in 28 days.
1.6 SUSTAINABLE DESIGN REQUIREMENTS
1.6.1 Local/Regional Materials
NOTE: Using local materials can help minimize transportation impacts, including
fossil fuel consumption, air pollution, and labor.
Use materials or products extracted, harvested, or recovered, as well as manufactured, within a [500][_____]
mile [800][_____] kilometer radius from the project site, if available from a minimum of three sources.
1.6.2 Environmental Data
NOTE: ASTM E 2129 provides for detailed documentation of the sustainability
aspects of products used in the project. This level of detail may be useful
to the Contractor, Government, building occupants, or the public in assessing
the sustainability of these products.
[Submit Table 1 of ASTM E 2129 for the following products: [_____].]
PART 2 PRODUCTS
2.1 UNIT COOLERS
[Forced circulation] [Free delivery] type, factory fabricated, assembled and tested, and packaged in accordance
with AHRI 420.
2.1.1 Construction
Construct casings of Type 300 Series stainless steel, aluminum, mill galvanized or hot-dip galvanized steel after
fabrication. Provide zinc coated carbon steel with protective coating. Direct or V-belt drive fans of the propeller
or centrifugal type. Statically and dynamically balance the fan wheels. Coils service shall have copper tubes
and aluminum fins. Provide water-tight, corrosion resistant drain pans. Drain pans and drainage piping for
units in spaces maintained at less than 2 degrees C 35 degrees F shall be insulated and fitted with means for
defrosting and condensate removal.
2.1.2 Energy Performance
NOTE: The Energy Policy Act of 2005 requires new buildings to use 30 percent
less energy than the ASHRAE 90.1 level. Efficient cooling equipment and components
contribute to the following LEED credits: EA Prerequisite 2; EA1.
Size equipment based on Design Manual CS from the Air Conditioning Contractors of America; do not oversize.
Equipment efficiency shall be in accordance with ASHRAE 90.1 - SI ASHRAE 90.1 -
IP, at a minimum.
2.1.3 Defrosting
Defrost units mounted in spaces maintained at 2 degrees C 35 degrees F or higher with ambient space air. Provide
units mounted in spaces maintained at less than 2 degrees C 35 degrees F with [hot gas] [electric heat] defrosting
system. Control room air defrosting by a timer defrost controller adjustable for up to 6 defrost cycles per
24 hours, each of 5 to 120 minutes duration. Defrost systems shall be controlled by [timer] [demand] defrost
controller.
2.1.3.1 Timer Defrost Controller
Controller shall include an adjustable timer to control frequency of cycles; [defrost initiating thermostat;]
adjustable program timer to control sequence of defrost cycle; [defrost terminating thermostat;] manual override
switch; selector switch; and status pilot light.
2.1.3.2 Demand Defrost Controller
Controller shall include an automatic, solid-state circuitry to initiate defrost cycle based on sensing adjustable
temperature difference of air moving across coil in direct proportion to frost build-up; thermostat to terminate
defrost; adjustable lockout to prevent initiation of defrost during pull-down after defrost cycle; manual override
switch; and status pilot light.
2.2 [COMPRESSOR] [CONDENSING] UNITS
NOTE: HFC-134a refrigerant is non-ozone depleting, but contributes to global
warming. HCFC-123 refrigerant is ozone-depleting (but much less so than R-11),
and contributes minimally to global warming. EPA, per the Significant New Alternative
Policy rule, reviews refrigerant substitutes on the basis of ozone depletion
potential, global warming potential, toxicity, flammability, and exposure potential.
Lists of acceptable and unacceptable substitutes are updated several times each
year. A chronological list of SNAP updates is available at http://www.epa.gov/ozone/snap/refrigerants/lists/index.html
or from the stratospheric ozone information hotline at 1 (800) 296-1996. Reducing
ozone depletion and global warming potential by reducing or eliminating CFC,
HCFC, and Halon use in air conditioning equipment contributes to the following
LEED credits: EA Prerequisite 3; EA4.
Factory fabricated, assembled and tested, packaged, ready for full capacity operation after terminal point connection
and field charging with operating fluids. Units shall conform to AHRI 520, ASHRAE 23, and ASHRAE 15 & 34
. Provide two charges of lubricating oil for each compressor. The first charge shall be used during the operating
test period, and at the end of this period shall be withdrawn and replaced with the second charge. Equipment
using R-11, R-12, R-113, R-114, R-115, or R-500 as a refrigerant will not be permitted. Refrigerants shall have
an Ozone Depletion Factor (ODF) of 0.05 or less. The ODF shall be in accordance with the "Montreal Protocol
on Substances that Deplete the Ozone Layer," September 1987, sponger by the United Nations Environment Program.
CFCs [and HCFCs] [and Halons ]shall not be permitted. Refrigerant shall be an approved alternative refrigerant
per EPA's Significant New Alternative Policy (SNAP) listing. [Use HFC-134a refrigerant.][Use HCFC-123 refrigerant.]
2.2.1 Capacity Criteria
NOTE: Show the capacity and saturated suction temperature, saturated condensing
temperature, superheat, and subcooling on the drawings.
Application capacity rating shown shall include suction superheat and liquid subcooling. Compressor design saturated
condensing temperature and saturated suction temperature limits shall not be exceeded.
2.2.2 Reciprocating Compressors
[Hermetic] [Open], [direct] [V-belt] drive reciprocating piston type, designed and constructed for indicated
compression ratio service. [Design welded hermetic compressors for high compression ratio heat pump and low
temperature refrigeration service.] Machine cylinder blocks and heads from aged, fine-grained, cast iron. [Provide
ammonia service compressor cylinder blocks and heads with self-draining water- or refrigerant-cooled jackets
where recommended by the manufacturer.] [Freeze-protect water jackets.] Forge crankshafts of steel or cast nodular
iron. Dynamically balance rotating parts, including crankshaft and power transmission components. Design compressors
to operate at partial loads without vibration greater than full load vibration and be capable of continuous operation
at lowest partial load. Piston speed shall not exceed manufacturer's recommendation or 4 1/2 m/s 875 fpm, whichever
is lesser. Provide main journals and ferrous and bronze connecting rods with replaceable sleeve insert type,
steel-backed, antifriction metal wear surface bearings, or antifriction bearings or a combination thereof. Aluminum
connecting rod bearings shall be integral or replaceable sleeve insert type. Provide bulls-eye type oil sight
glass at crankcase operating level. Compressors with a rated input of 2 1/4 kW 3 horsepower and over shall have
forced-feed lubrication with reversible, self-priming, suction strainer fitted, direct crankshaft drive, positive-displacement
pump. [Open compressor shaft seals shall be oil lubricated and cooled rotary mechanical type with externally,
individually, replaceable wearing components.] External drive motor enclosures shall be [open drip-proof.] [totally
enclosed.]
2.2.3 Helical Rotary Compressors
Provide positive displacement, oil-injected type, driven by an electric motor. Solid steel rotors, Society of
Automotive Engineers Grade 1141 or 1144. Shaft main bearings shall be either sleeve-design type with leaded
bronze or steel-backed babbit; or frictionless bearing design, ball or roller type. Provide housings and covers
of high-grade cast-iron pressure castings. Lubrication systems shall lubricate rotors, bearings, shaft seal
as well as rotor sealing and cooling. Provide an oil safety cutout interlocked with the compressor starter to
allow compressor to operate only when the oil management system is operational. Provide for lubrication of bearings
and shaft seals on shutdown with or without electric power supply.
2.2.4 Accessories
Unit accessories with 1 1/8 kW 1 1/2 horsepower and larger compressor shall include suction, discharge and liquid
gage ported shutoff valves, suction and discharge service valves, suction strainers, mufflers, crankcase heaters,
and pressure relief. Provide double seated service valves with gage ports. Provide lube oil pressure gages
and failure switches for forced-feed lubricated open and accessible hermetic compressors. Unless continuous
heating is recommended by compressor manufacturer, crankcase heaters shall function only when compressor is stopped.
[Provide condensers with purge valves.] [Where low ambient control incorporates condenser flooding, receiver
shall be sized as required.]
2.2.5 Capacity Controls
Compressors shall start from rest unloaded. [Provide with start-stop control.] [Provide with capacity modulation.]
[Provide not less than [_____] capacity control steps.]
2.2.6 Condenser, Integral
Provide with [air-cooled] [water-cooled] condenser. [Open compressor unit rated through 2 1/4 kW 3 horsepower
may utilize integrally cast blades of compressor flywheel or sheave as the air moving device supplemented by
a propeller fan mounted on extended compressor drive motor shaft.] [Provide condensers and compressors with
manufacturer's standard direct-drive propeller fans which are elastomer mounted in combined, enclosing, guard
or support.] Construct coils with separate subcooling circuit [and circuiting as indicated,] of copper tubing
with aluminum fins. Test coils in accordance with ASHRAE 15 & 34. Provide coils with sheet steel frame
and venturi fan shroud.
2.2.7 Condenser, Water-Cooled, Integral
Provide cleanable tube-in-tube condenser with [copper] [70/30 copper-nickel] coolant wetted surfaces and coolant
regulating valve. Base condenser rating on coolant fouling factor of [0.0005] [0.001].
2.2.8 Condenser-Receiver, Water-Cooled, Integral
NOTE: Normally 70/30 copper nickel performance is superior to 90/10 copper
nickel in brackish and salt water. Where conditions are not detrimental to
90/10 copper nickel, incorporate same as an alternative acceptable material.
Use the higher fouling factor for open systems.
Provide cleanable shell and tube condenser-receiver with [copper] [70/30 copper-nickel] tubes and coolant regulating
valve. Base condenser rating on coolant fouling factor of [0.0005.] [0.001.]
2.2.9 Control Panels
NOTE: Verify that reverse-phase, and phase imbalance protection provisions
are available in sizes under 70 kW 20 tons. Check with manufacturers before
specifying other than across-the-line starting.
Control panels and electrical components shall conform to NFPA 70,NEMA ICS 1, NEMA ICS 2, NEMA ICS 3, NEMA ICS 4
and NEMA ICS 6, and mounted in a NEMA ICS 6, Type 1 enclosure. Electrical controls shall include [[fused] [unfused]
disconnect;] control transformers with 50 percent excess capacity; main and branch circuit overload protective
devices compensated for ambient temperatures as recommended by the manufacturer; reverse phase protection where
necessary to preclude damage; single-phase and phase-imbalance protection; low voltage protection; manual reset
on power interruption or safety shutdown; [power factor correction capacitors;] [status pilot lights;] compressor
safety, operating and capacity controls; [defrost controls;] [local and remote audible and visual alarms with
provisions to silence;] short cycling control with lock-out timer; time delay for sequenced compressor starts;
remote component interface; and intercomponent wiring to terminal blocks with 10 spares. Provide stranded copper
wire of required ampacity and insulation at encountered temperatures. Identify wires at terminal points.
2.2.10 Base Mounting
NOTE: Where condensing units or compressors are located on top of walk-in boxes,
mount on spring vibration isolators. Weight of inertia block shall be an engineered
solution accommodating site conditions.
Mount compressors and components on a rigid, fabricated steel [base,] [rack,]. [Mount compressor assembly to
the base on spring type vibration isolation mountings. Mount the base on the floor on elastomer pads.] [Mount
assembly supporting base on [cantilevered, height reducing,] spring type vibration isolation mountings, selected
to limit transmissibility of imbalanced forces at lowest equipment revolutions per minute to 5 percent.] [Mount
assembly on concrete inertia block, fitted with cantilevered, height reducing, spring type vibration isolation
mountings. Weight of concrete inertia block shall be [2.0] [_____] times weight of supported assembly. Select
spring mountings to limit transmissibility of imbalanced forces at lowest equipment revolutions per minute to
3 percent.] [Integral-to-unit pipe or tubing, and conduit connection to [control panel] [and] [building services]
shall be through service rated flexible connectors.]
2.3 CONDENSERS, AIR-COOLED
NOTE: Currently, lowest SRN ratings, in the order of 16 or 17, occur in units
rated under 19,045 kW 65 MBH. Largest "quiet" equipment ratings are in 19-20
range.
Factory fabricated and tested, packaged, self-contained and ready for full capacity operation after terminal
point connections. Unit [shall be manufacturer matched part of split system, and] shall conform to AHRI 460,
AHRI 210/240, and AHRI 270. Unit shall produce a Sound Rating Number (SRN) not greater than [16] [21] [_____].
2.3.1 Capacity Rating
Size the condenser for the capacity and conditions indicated. Do not oversize.
2.3.2 Energy Performance
NOTE: The Energy Policy Act of 2005 requires new buildings to use 30 percent
less energy than the ASHRAE 90.1 level.
Equipment efficiency shall be in accordance with ASHRAE 90.1 - SI ASHRAE 90.1 -
IP, at a minimum.
2.3.3 Unit Casing
Construct casing of galvanized steel or aluminum sheet metal and galvanized or aluminum structural members.
Provide with lifting provisions, access panels, removable legs, [discharge hood,] and fan and heat rejection
coil guards and screens.
2.3.4 Finishes
Equipment and component items, when fabricated from ferrous metal, shall be factory finished with the manufacturer's
standard finish, except that items located outside of buildings and subject to a salt atmosphere shall have weather
resistant finishes that will withstand 240 hours exposure to the salt spray test conducted in accordance with
ASTM B 117, using a 20 percent sodium chloride solution. Immediately after completion of the test, the specimen
shall show no sign of blistering, wrinkling, cracking, or loss of adhesion and no sign of rust creepage beyond
3.18 mm 1/8 inch on either side of the scratch mark.
2.3.5 Fans
2.3.5.1 Propeller Fans
Propeller type fans shall be [direct] [V-belt] drive type with dynamically balanced, adjustable or fixed pitch,
aluminum or corrosion protected steel blades. [V-belt drive wheels shall be mounted on corrosion protected drive
shaft supported by grease lubricated antifriction bearings with cast ferrous pillow block or extended housing.]
Each wheel drive shall be independent of any other wheel. Extended lubricant lines shall be provided for maintenance
access. Drive bearings shall be protected with water slingers or shields.
2.3.5.2 Centrifugal Fans
[Forward curve] [Backward inclined] centrifugal scroll type fans shall be provided with streamlined orifice inlet
and V-belt drive, limited to three wheels mounted on a corrosion protected drive shaft. Wheels and housing shall
be fabricated from aluminum or galvanized steel. Wheels shall be dynamically balanced. Fan shaft first critical
speed shall be not less than 25 percent greater than operating speed. Fan shaft shall be mounted in grease lubricated
antifriction bearings with cast ferrous pillow block housing. Extended lubricant lines shall be provided for
maintenance access.
2.3.5.3 Fan Drives
V-belt drives shall be fitted with guards, [fixed pitch] [or] [adjustable pitch] sheaves.
2.3.6 Fan Motors
Motors less than 3/4 kW 1 hp shall meet NEMA High Efficiency requirements in accordance with NEMA MG 1. Motors
3/4 kW 1 hp and larger shall meet NEMA Premium Efficiency requirements in accordance with NEMA MG 1. Motors
shall be variable speed. Motor enclosures shall be [open drip-proof] [totally enclosed] type. Motors and bearings
shall be protected by location or with water slingers or shields.
2.3.7 Refrigerant Circuit
Refrigerant containing components shall comply with ASHRAE 15 & 34, shall be factory tested, cleaned, dehydrated,
charged, and sealed. Each condenser coil connection shall be fitted with a manual isolation valve of the ball
type and an access valve on the coil side. Receiver shall conform to AHRI 495. [Receiver shall be insulated
with not less than 25 mm 1 inch thick, 100 percent adhesive bonded, vaportight, flexible, closed-cell elastomer
and finished with two coats of solvent base PVC protective coating or 0.41 mm 0.016 inch thick aluminum jacket.]
2.3.8 Coils
Coils shall be constructed of copper or aluminum tubing with permanently attached fins for thermally efficient
contact. Indoor and outdoor coils shall be matched and from same manufacturer. Use a low sensible heat ratio
for more moisture removal. Casing shall be galvanized steel or aluminum. [Coils for service in corrosive or
salt laden atmosphere shall be constructed of aluminum or with copper tubes and fins and galvanized end sheets.]
[In addition, coils shall be protected with baked-on, minimum 0.076 mm 3 mil thick, phenolic coating.] [Separate
condenser circuit shall be provided for each compressor complete with separate controls for each related fan.]
[Unit shall provide not less than [_____] degrees C degrees F subcooling.] Subcooling circuit shall be liquid
sealed. Condenser may be used for refrigerant storage in lieu of separate receiver, provided that storage capacity
is 20 percent in excess of fully charged system. Where liquid flooding low ambient control is furnished, a separate
receiver shall be provided.
2.3.9 Low Ambient Condenser Controls
Unit shall be capable of operating in ambient temperature of [_____] degrees C degrees F. Controls shall permit
proper operation of system with proper differential pressure across thermostatic expansion valve. Control system
shall be based on sensing of actual condensing pressure in conjunction with manufacturer's method of fan or damper
control or by flooding the condenser. [Multifan units with power operated fan discharge dampers, shall include
gravity dampers.] [Electric damper operator torque shall be at least 2.0 times required torque.] [Air volume
control is not acceptable for ambient conditions below 2 degrees C 35 degrees F.] Controls shall be set to produce
a minimum 21 degrees C 70 degrees F saturated refrigerant condensing temperature.
2.3.10 Control Panels
Unit mounted control panels shall be housed in NEMA ICS 6, Type 1 or 3A enclosures. Controls shall include [control
transformer,] [fan motor [contactor] [starters],] [solid-state speed control,] overload protective devices, interface
with local and remote components, miscellaneous electric devices, and intercomponent wiring to terminal block
points.
2.4 CONDENSERS, WATER-COOLED
Condenser shall be [remote mounted] [and] [integral to water-cooled condensing unit] and shall conform to AHRI 450
.
2.4.1 Capacity Criteria
Ratings shall be in Btuh heat rejection for AHRI 450 Group [1] [3] conditions, and for application at indicated
design conditions. Ratings shall be based on [0.0005] [0.001] cooling water side fouling factor at design velocity.
Coolant side pressure drop at design condition flow and fouling factor shall not exceed that indicated and shall
be based on tube-side velocities of not less than 1.07 nor greater than 2.44 m/s 3.5 nor greater than 8 fps.
When condenser is used for refrigerant storage during pumpdown, system charge shall be held within 80 percent
of unit volume and storage capacity shall be stated. [Condensers shall be designed for coolant side working
pressure of not less than [690] [1034] kPa (gage) [100] [150] psig, refrigerant side working pressure of not
less than 2068 kPa (gage) 300 psig.] A portion of entering coolant shall be in heat transfer contact with liquid
refrigerant to provide [_____] degrees C degrees F subcooling. Do not oversize equipment.
2.4.2 Energy Performance
NOTE: The Energy Policy Act of 2005 requires new buildings to use 30 percent
less energy than the ASHRAE 90.1 level.
Equipment efficiency shall be in accordance with ASHRAE 90.1 - SI ASHRAE 90.1 - IP, at a minimum.
2.4.3 Shell and Tube Type
Condensers shall be of the shell and tube type with the coolant in the tubes. The design pressure drop shall
govern the number of passes. Condenser heads shall have pipe connections which permit access to or removal of
the tubes. Materials of construction shall be suitable for the service in which used. Condensers shall conform
to AHRI 450, with safety provisions conforming to ASHRAE 15 & 34. Where coolant may be subject to freezing,
condensers shall be gravity drainable and shall be fitted with automatic drain and vent valves.
2.4.4 Coolant Control
Control valves shall be [automatic, self-contained, controlled by condensing pressure, and shall close bubble-tight
when compressor is not operating.] [modulating three-way mixing type, controlled by pressure controller.] [Atmospheric
cooling equipment shall be deenergized at indicated set point.] Control shall be set for a saturated refrigerant
condensing temperature of 21 degrees C 70 degrees F.
2.5 ATMOSPHERIC COOLING EQUIPMENT
[Cooling tower] [Evaporative water cooler] [Evaporative condenser] shall be [induced] [or] [forced] mechanical
draft, [vertical] [horizontal] discharge [parallel-flow] [counter-flow] [or] [cross-flow] type of fire-resistant
construction. Cooling equipment shall be factory fabricated, assembled and tested. [Cooling tower shall conform
to requirements of CID A-A-59223, except as modified hereinafter.]
2.5.1 Design and Performance Requirements
NOTE: When 53 m/s 10,500 fpm velocity is exceeded, noise may become a significant
factor. Low tip speeds may or may not increase size of cooling tower. Consider
probability of chemically-treated high-dissolved-solids drift loss causing damage
to adjacent structures and environment (trees, shrubs, etc.).
The requirements of CTI ATC-105 shall be the basis of establishing unit capacity and performance. Unit capacity
shall include a site recirculation factor. Performance wind velocity shall be 8 km 5 miles per hour. Drift
loss shall not exceed 0.1 percent of unit circulation rate. Minimum unit design wind load shall be [146 kg per
square meter] [30 pounds per square foot] [_____]. [Minimum design fan deck live load shall be [195 kg per square
meter] [40 pounds per square foot] [_____].] Fan tip speed shall not exceed [53 mps] [10,500 feet per minute]
[_____]. Design and construction of steel members shall conform to AISC 360 and AISI SG03-3.
2.5.2 Materials of Construction
Metallic materials of construction shall be mill galvanized or hot-dip galvanized after fabrication. Plastics
shall have an ASTM E 84 flame spread rating of 25 or less, except as otherwise specified.
2.5.3 Framework and Casing
Structure shall withstand maximum stresses imposed. Panel joints shall drain to interior. Seals, fasteners,
and flashing shall be provided to preclude external to unit water leakage. [Discharge cylinder height shall
be not less than [_____] mm inches above fan deck.]
2.5.4 Inlets and Louvers
Louver material shall be of thickness, configuration and support span to prevent flutter or sagging under loads
imposed during operation. Inlet shall be fitted with square mesh galvanized hardware cloth with minimum 80 percent
open area.
2.5.5 Distribution System
Hot-water distribution system shall be [open basin] [or] [pressurized spray nozzle] type. [Open basin shall
be designed to permit surge water flow 40 percent greater than specified flow without overflow of basin. Basin
shall be fitted with removable cover.] System shall be self-draining and nonclogging. [Means to isolate and
balance flow to each section of unit shall be provided.]
2.5.5.1 Pumps
Pump casing shall be designed to withstand discharge head indicated, plus static head on system, plus 50 percent
of the total, but not less than 862 kPa (gage) 125 psig. Motor shall not be overloaded with pump operating at
any point on its characteristic curve, and shall have [open drip-proof] [totally enclosed] enclosure. Pump speed
shall not exceed [1800] [3600] revolutions per minute. Pumps shall be [horizontal split-case] [end-suction vertical
split-case] [close-coupled in-line] centrifugal type. Casing and bearing housings shall be cast ferrous metal.
Casing shall be fitted with manual air vents and drain plugs. [Suction and discharge shall be provided with
pressure gage taps.] Shaft seal shall be mechanical type. Impeller and trim shall be bronze. Shaft shall be
stainless steel or carbon steel sleeved with stainless steel. Bearings shall be sealed, grease lubricated, antifriction
type. Pump shall be accessible for servicing without disturbing piping connections. [Pump and motor shall be
mounted on a common cast iron or fabricated structural steel base having lipped edges and tapped drainage openings.]
[Pump shall be provided with elastomer-in-shear type shaft coupling with guard.] [Close-coupled pumps shall be
provided with drip pockets and tapped openings.] Pump rotating assembly shall be dynamically balanced.
2.5.6 Heat Exchangers
[Evaporative condenser coil shall comply with ASHRAE 15 & 34]. Coils shall be completely drainable [serpentine]
[or] [straight length, individually cleanable] type. Coil tubes and headers shall be [seamless deoxidized copper]
[or] [electric resistance welded, hot rolled, mill scale free, carbon steel tube and header, externally hot-dip
galvanized after fabrication to provide not less than 0.70 kg of zinc per square meter 2.3 ounces of zinc per
square foot of single side surfaces]. [Coil tubes shall be Schedule 40 carbon steel, internally cleaned to remove
mill scale and particulate and externally hot-dip galvanized after fabrication to provide not less than 0.70
kg of zinc per square meter 2.3 ounces of zinc per square foot of single side surfaces.] [[Split- ] [Multi]
[circuit] ] [desuperheater] [subcooling] [refrigerant and jacket cooling water] coils shall be provided as indicated.
[Refrigerant subcooling circuit shall produce [_____] degrees C degrees F of subcooling.] Refrigerant receiver
shall conform to requirements of AHRI 495. [Receiver insulation shall be not less than 25 mm 1 inch thick, 100
percent adhesive bonded, flexible, closed-cell elastomer, and finished with two coats of solvent base PVC protective
coating.] [Copper coils shall) be dielectrically isolated.] Header connections shall be fitted with [thermometer
wells,] [pressure gage taps,] and [manual] [automatic] vent connections. Heat exchanger shall be pressure and
temperature rated and tested to the same fluid service standards and codes as connecting external piping.
2.5.7 Fill
Fill for cooling tower shall be minimum [0.38 mm15 mil thick corrugated or molded PVC plastic] [0.48 mm19 mil
thick chloroprene bound asbestos sheet], in honeycomb or wave form, impregnated with melamine or chlorinated
rubber, having an ASTM E 84 flame spread rating of 5 or less. Fill shall be supported to prevent sagging or
misalignment.
2.5.8 Eliminators
Metal eliminators shall be not less than 24 gage steel. Nonmetallic eliminators shall conform to requirements
specified for fill.
2.5.9 Cold Water Basin and Accessories
Basin shall be constructed of steel [, and shall be sized for dry-basin operation] [, and shall be sized to have
sufficient water capacity and free-board to prevent [pump cavitation,] air-entrainment and to accommodate run-back
without overflow]. Basin assembly shall be water-tight. [Multiple basins shall operate as one basin with common
water level and shall be complete with interconnecting piping.] Basin outlet screen shall be constructed of
galvanized, 13 mm 1/2 inch square mesh hardware cloth, reinforcement, and framing. Basin shall be fitted with
overflow and valved drain. [Manufacturer's standard modulating float-controlled makeup valve shall be provided.]
[A nonmodulating, pilot actuated, float-controlled, diaphragm type makeup valve shall be provided where a water
meter is indicated or specified in the makeup supply line.] Makeup shall discharge 50 mm 2 inches or two pipe
diameters, whichever is greater, above maximum attainable basin water level during overflow condition, or as
required to preclude backflow. A drainable 20 mm 3/4 inch hose bib connection shall be provided with a vandalproof
vacuum breaker for makeup line mounting. [Basin shall be fitted with indicated heaters.]
2.5.10 Access and Safety Provisions
Unit shall be fitted with access provisions as indicated to facilitate inspection, maintenance and replacement
of components. Guard screens shall be provided at unducted fan inlets and far discharge. Guards shall be provided
for moving power transmission components.
2.5.11 Fans and Drives
[Induced draft counter-flow and cross-flow cooling tower fans shall be propeller type and drive shall be [gear
type with motor out of wet airstream] [or] [belt type with motor [in] [out of] wet airstream].] [Induced draft
evaporative [water cooler] [condenser] fans shall be propeller type and drive shall be [gear] [belt] type with
motor out of wet airstream.] [Forced draft fans shall be propeller or centrifugal type, with multiple V-belt
drive and motor out of wet airstream.]
2.5.11.1 Propeller Fans
Shall be airfoil section type with fixed or adjustable pitch blades fabricated from solid aluminum alloy, except
fans sized 1220 mm 48 inches and under may be manufacturer's standard. Fixed pitch fans combined with gear drives
are not acceptable. Adjustable pitch fans, with pitch set at or near maximum pitch, combined with gear drives,
are not acceptable. Fans shall be statically or dynamically balanced to limit imbalance forces on drive shaft.
2.5.11.2 Centrifugal Fans
Shall be forward curve, double-inlet, drainable scroll type with streamlined inlets, constructed of galvanized
or stainless sheet steel or aluminum. Fan shaft shall be corrosion protected. Bearings shall be double-shielded,
grease lubricated, self-alining, ball or roller, cast iron (split-bolted), pillow block housed, antifriction
type. Sleeve bearings may be used in conjunction with one or more antifriction bearings at locations other than
drive-end. Sleeve bearings shall be oil-lubricated, grooved, cast iron housed, antifriction metal liner type,
with an effective length at least two times shaft diameter. Fan wheel assembly shall be dynamically balanced.
Lubrication of bearings shall be safely accomplished while unit is operating. Oil lubricated sleeve bearings
shall be fitted with reservoir.
2.5.11.3 Gear Drive Speed Reducer
Shall have a service factor of not less than 1.5 and shall be reversible. Oil level, vent and drain lines shall
be nonferrous metal, vibration isolated, and extended to maintenance access points. Nonlubricated, dynamically
balanced, floating shaft and couplings shall be provided. Construction shall be stainless steel or corrosion
protected metals.
2.5.11.4 Fan Shafts
Wet service belt drive fan shaft shall be supported by drip and splash protected, grease lubricated, split-bolted,
pillow block antifriction bearings. Lubrication provisions shall include automatic grease relief to visible
point and grease supply fittings extended to permit lubrication under operating conditions. Belt drive shall
be [reversible,] one-piece, integral-back, multiple-groove type, constructed of synthetic fabric or fiber reinforced
neoprene.
2.5.11.5 Motors
Motors less than 3/4 kW 1 hp shall meet NEMA High Efficiency requirements in accordance with NEMA MG 1. Motors
3/4 kW 1 hp and larger shall meet NEMA Premium Efficiency requirements in accordance with NEMA MG 1. Motors
shall be variable speed. Enclosure shall be totally enclosed, [single] [two] speed, [nonreversing] [reversing]
type, fitted with 120 volt a.c. resistance heaters. [Reversing starters shall be fitted with adjustable time
delay deceleration relays.] Manufacturer's standard, adjustable set point, manual reset type vibration cut-out
switch shall provide to deenergize fans upon excessive vibration.
2.5.12 Vibration Isolation
Unit shall be vibration isolated from supporting structure by mountings which limit imbalanced force transmissibility
to [5] [_____] percent at lowest equipment revolutions per minute.
2.5.13 Corrosion Protection
Galvanize cast and wrought ferrous metal in accordance with [ASTM A 123/A 123M] [ASTM A 653/A 653M]. Sheared
edges shall receive additional corrosion protection of a zinc rich coating. Other steel items specified to be
galvanized shall be coated in accordance with ASTM A 153/A 153M.
2.5.14 Capacity Control
Unit shall be fitted with [modulating manual] [vortex] [inlet] [internal bypass] [and discharge] damper controls
[in addition to [on-off] [fan] [and] [pump] [cycling] [and] [fan motor speed control]]. Dampers shall be constructed
of aluminum or galvanized, steel and fitted in such a manner as to preclude freeze-up, mechanical binding or
corrosion. Dampers shall be fitted with a non-lubricated damper shaft bearings; corrosion resistant damper shaft
journals and pivots; pre-lubricated, antifriction, ball type adjustable linkage; [NEMA Type 4 limit switches;]
[waterproof electric operator torque shall be not less than 2.0 times required torque;] and temperature sensing
control system with output controlling damper position.
2.6 AUTOMATIC CONTROLS
Temperatures in the refrigerated rooms shall be regulated by room thermostats and electric solenoid valves in
the refrigerant supply piping to the evaporators. Compressors for each system shall operate on suction pressure
switches, functioning in such a manner as to cut in and cut out compressors as the suction pressure rises above
or falls below predetermined operating conditions. Provide a multiple step controller for multiple compressor
units in a single system.
2.6.1 Temperature Control Cabinets
Provide the necessary controllers, relays, clocks, alarms, and temperature gages in or on the face of control
cabinets for each system. Construct cabinets of steel or aluminum with hinged door and lock. Provide temperature
gages, pressure switches and pilot lights flush on the cabinet door. Provide controllers and relays in the interior
of the cabinet on a steel or aluminum subpanel which shall also act as the back of the cabinet. Electrical controls
shall be prewired to numbered screw type terminal strips. Cabinets shall be [floor-mounted free-standing type]
[or] [integral with refrigeration compressor unit control panels].
2.6.2 Safety Cutout Switches
Provide automatic high pressure, low oil level, and compressor overload safety cutout switches for each compressor.
The switches shall be located in the condensing unit control panel. The cutout switches shall automatically
stop the respective compressors and simultaneously ring an alarm bell whenever the pressure within the condenser
rises above the predetermined safe point.
2.6.3 Thermostats
Shall be of a lock shield type suitable for operation in connection with its respective solenoid valve. The
thermostats shall maintain the temperature of the refrigerated rooms within a maximum range of plus or minus
one degrees C 2 degrees F. The thermostats shall be of the adjustable type, with gas filled tube. The thermostats
shall have temperature range of minus 34 degrees C to plus 10 degrees C 30 degrees F to plus 50 degrees F. Thermostats
shall be mounted adjacent to interior door, unless otherwise indicated.
2.6.4 Controllers
2.6.4.1 Differential Pressure
Controller shall be provided with high and low pressure sensing ports and shall be direct or reverse acting with
calibrated proportional band and set point adjustments. Controller output shall be [low voltage electric] [pneumatic]
[4-20 mA dc], proportional to the pressure differential sensed. Local and remote set point adjustments shall
be included. Range shall be as required to meet system requirements.
2.6.4.2 Differential Temperature
Controller shall be provided with two filled, remote sensing bulbs connected to the controller by [armored] capillary
tubing. Controller shall be direct or reverse acting with calibrated proportional band and set point adjustments.
Controller output shall be [low voltage electric] [pneumatic] [4-20 mA dc], proportional to the temperature differential
sensed. Provisions for local and remote set point adjustments shall be included. Range shall be as required
to meet system requirements. For immersion service, thermal wells shall be provided.
2.6.5 Pilot Lights
Panel mounted pilot lights shall be NEMA Class 12 oil-tight, push-to-test transformer type for 6-8 Vac lamps.
Lamps shall be replaceable by removal of color cap. Caps color shall be as indicated.
2.6.6 Programmer, Demand Control/Load
NOTE: Before application of energy management systems/load shedders to refrigeration
systems, and related fans and pumps, the designer shall ascertain that application
will not be conducive to equipment damage and counterproductive. Safety trips,
compressor slugging, freeze-ups and reloading of circuits may occur.
Programmer shall be fully automatic, fail safe, field programmable, solid-state, demand control and load programming
for [_____] [16] loads. Demand control portion shall monitor power consumption by [watt] [or] [current] transducers.
Set point shall be field adjustable with adjustable dead band. Load shedding sequence time and differential
time between load shedding shall be adjustable. Contacts shall store alarm condition. Meter readout shall indicate
demand deviation from set point. Load profile recorder shall be strip chart type with readily discernable event
record. Load programmer shall permit programming of on/off time of each load for any time element within a week
and shall equalize power demand over a preset time cycle. System shall include input override and time cycle
accelerator for checkout. Alarm condition, status of loads and time period shall be visually indicated and recorded.
Each load shall include a H-O-A toggle switch. Alarm provisions shall include relay contacts for external, remote
alarm functions and test provisions. Override [thermostat] [pressure switch] [timer] shall be provided to restore
shedded loads indicated. Control panel enclosure shall be NEMA ICS 6, Type 1, surface mounted type with key
lock. Load profile recorder shall be [surface] [flush panel] mounted type. Load relays shall be plug-in type
with critical load failure in "on" mode and contacts rated for pilot duty at 120 volt a.c. Load shedding position
switches shall shed loads on a first shed/last restore basis and remove loads from system logic for shedding
cycle. Time clock shall be fitted with spring motor to maintain time in event of power failure.
2.6.7 Switches, Fluid Service
Switches shall be field adjustable SPDT type and shall have NEMA ICS 6, Type 1 enclosure with operating range
specified or indicated. Circuits shall be as required for the applicable functions.
a. Provide air flow switches with a service pressure range of 30 to 2940 Pa 0.12 to 10 inches
water gage.
b. Provide water flow switches with a body rating suitable for the service, field adjustable
activating flow rate, and a pressure drop not in excess of 13.8 kPa 2 pounds per square inch
at maximum flow rate.
c. Pressure switches shall be factory set, one or two stage as indicated, with adjustable operating
and differential pressure. Bourdon tube inlet shall be fitted with damper screw adjustment.
d. Differential pressure switches shall be factory set, provided with high and low sensing
ports, one or two stages and adjustable differential range and pressure.
e. Temperature switches shall be factory set, provided with [armored] capillary tubing and
filled sensing system, one or two stages as indicated, and operating adjustable differential
range. For immersion service, thermal wells shall be provided.
f. Differential temperature switch shall be factory set, provided with two separate, [armored]
capillary systems, one or two stages, and adjustable differential range and temperature. For
immersion service, thermal wells shall be provided.
2.6.8 Push-Button Stations
Stations shall be NEMA Class 12 oil-tight, momentary or maintained contact type, as indicated. Start-push-buttons
shall have a fully guarded or flush black operator button. Stop-push-buttons shall have an unguarded or extended
red operator button.
2.6.9 Selector
Switches shall be NEMA Class 12 oil-tight, momentary or maintained contact type, as indicated, with standard
operator.
2.7 HEAT RECOVERY DEVICES
Water heater shall be double-wall, tube-within-tube heat exchanger type, complete with thermostatic control.
[Heater shall be provided with [refrigerant compressor head pressure control] [and] [interlocked, potable water
circulating pump].] [Cabinet shall be fabricated of zinc protected steel and shall be internally insulated in
coil space.] Heat exchanger coil shall consist of an external refrigerant containing carbon steel tube and an
internal, double-wall-in-metallic contact, convoluted, potable water containing copper tube. [Pump and motor
assembly shall be close-coupled, manufacturer's standard type with indicated head and capacity characteristics,
and with brass, bronze, copper or stainless steel wetted parts.] Pump shall be [remotely mounted and] rated
for [115] [208] [230] volt a.c. power supply. [Heat exchanger shall be sized to extract not more than [_____]
[25] percent [of the superheated portion] of the total rated condenser load.]
2.8 MOTORS
Provide continuous duty rated motors conforming to NEMA MG 1. Unless otherwise specified, motor synchronous
speed shall be 1800 rpm. Motors less than 3/4 kW 1 hp shall meet NEMA High Efficiency requirements. Motors
3/4 kW 1 hp and larger shall meet NEMA Premium Efficiency requirements. Motors shall be variable speed. Refrigeration
compressor motors shall comply with compressor manufacturer's recommendations. Rate motors with nameplate power
less than 3/8 kW 1/2 hp for 115 volts, single-phase, 60 Hz power supply. Rate motors with nameplate power 3/8
kW 1/2 hp and greater as indicated. Extended voltage motors nameplated 208-230 and rated for 187-253 volts are
not acceptable. Provide NEMA Class B insulated polyphase motors, normal torque and starting current, Design
B, squirrel-cage induction type, except as otherwise specified. Provide Nema Design Class C when high starting
torque is required. [Provide [one] [two] -winding type two-speed polyphase motors.] Nameplate for polyphase
motors shall include efficiency index letter. Motor duty requirements shall allow for maximum frequency start-stop
operation and minimum encountered interval between start and stop. Motor torque shall be capable of accelerating
the connected load within 20 seconds with 80 percent of the rated voltage maintained at motor terminals during
one starting period. Provide [open drip-proof] [totally enclosed] [explosion-proof] motor enclosures. Polyphase
motor bearings shall be double-shielded, grease lubricated, antifriction type with provisions for radial and
thrust loads as imposed by application duty. Provide bearings with grease supply fitting and grease relief to
outside of enclosure. Single phase motor bearings shall be as specified for polyphase motors, except manufacturer's
standard prelubricated, sealed cartridge types are acceptable. Provide [across-the-line magnetic] [reduced voltage]
type motor startersconforming to NEMA ICS 1 and NEMA ICS 2.
2.9 POWER TRANSMISSION COMPONENTS
Fan and open compressor drives shall be [direct] [and] [V-belt] type as specified or indicated. Provide drives
in accordance with the manufacturer's published recommendations, except as otherwise specified. Base horsepower
rating of V-belt drives on maximum pitch diameter of sheaves. Provide compressors with fixed sheaves and drives
with a minimum service factor of [1.5] [2.0]. Drives with motors rated up to and including 7 1/2 kW 10 horsepower
shall be classical belt section, adjustable sheave type, with a service factor of not less than 1.5. Drives
with motors rated over 7 1/2 kW 10 horsepower [up to and including 22 3/8 kW 30 horsepower,] shall be classical
section, adjustable sheave type with a service factor of not less than 1.5. Where the number of unit starts
exceeds 8 per 24 hours, add 0.1 to the required drive service factor. Provide statically and dynamically balanced
sheaves, machined ferrous metal, bushing type, secured by key and keyway. Pitch diameter of fixed pitch sheaves
and adjustable sheaves, when adjusted to specific limits, shall be not less than that recommended by NEMA MG 1
. Select adjustable sheaves to provide the required operating speed with the sheave set at mid-point of its
adjustment range. The adjustment range for various size and type belts shall be 16 percent minimum for classical
section belts and 12 percent minimum for narrow section belts. Provide belt drive motors with slide rail or
equivalent adjustable motor bases. Provide manufacturer's standard direct drive couplings for motors rated less
than 2 1/4 kW 3 horsepower. For 2 1/4 kW 3 horsepowerand greater, direct drive couplings shall be elastomer-in-shear
type.
2.10 ALARM SYSTEM
Provide both audible alarms and trouble lights to indicate when an abnormal condition exists in each room. Locate
pushbuttons inside each room and adjacent to door. Alarm bell shall be located outside of each refrigerated
room and adjacent to door. Each refrigerant room having electric defrost shall be provided with a defrost compensator
which shall deenergize the abnormal condition alarm system during the defrost cycle; these devices shall be coordinated
with defrost time clock on the respective compressors. Systems shall detect a temperature rise above the designated
temperature or actuation of entrapment pushbutton and shall energize an alarm lamp and horn at cooler local alarm
panel.
2.10.1 Refrigeration Alarm System
Provide an electrically supervised refrigeration alarm system. Operation of any high-temperature alarm devices
shall cause an alarm to register as follows:
a. Lamp and horn at local alarm panel
b. Annunciator panel shall light up and identify which cooler is malfunctioning
c. Alarm bell shall ring
2.10.2 Refrigeration Local Alarm Panel
Provide local alarm panel adjacent to refrigerator. Alarm panel shall include alarm lamp, "power on" lamp, alarm
test switch, reset switch, an alarm line supervisory meter, alarm silencing switch, high temperature alarm device
entrapment manual switch, alarm horn, and required relays. System shall normally work off 120 volts a.c. and
transfer automatically to 24 volt d.c. operation in the event of power failure. The d.c. power shall be from
rechargeable batteries and operate the system for a minimum of 24 hours in supervisory condition and 15 minutes
in alarm condition. The power supply shall be capable of fully recharging the batteries (as well as powering
the system) within 36 hours.
2.10.3 Annunciator Panel
Provide an electrically supervised annunciator panel. Provide the panel adjacent to local alarm panel. Cover
shall be such as to prevent tampering and yet allow full viewing of annunciator lamps and zone identification
lettering. Detector loops shall be electrically supervised by the remote alarm panel. Panels shall be equipped
with terminals for all necessary wiring. Annunciator panel shall be so connected to detection panel so that
zone lights shall be battery-powered in case of electrical failure.
2.10.4 High Temperature Alarm Device
Each refrigerated room shall have a high temperature alarm device of the remote bulb type with minimum 1 1/2
meters 5 feet of capillary. Temperature range shall be minus 34 degrees C to plus 10 degrees C 30 degrees F
to plus 50 degrees F, with adjustable differential of not less than 2 to 5 degrees C 4 to 10 degrees F.
2.11 COOLING TOWER WATER TREATMENT SYSTEM
NOTE: If the activity has a cooling water treatment contract in effect, ensure
that the system specified is compatible with it.
Shall automatically feed chemicals, and bleed system water to prevent scale, corrosion, and biological growths.
The system shall include chemical feed pump, tank, bleed-off solenoid valve, electric impulse water meter, electric
timer, and conductivity controller. Provide a polyethylene tank and injection valve assembly for each feed pump.
2.11.1 Feed Pumps
Shall be positive displacement type with an adjustable capacity and discharge pressure not less than 1.5 times
the line pressure at the point of connection. Provide with pressure relief valve, and check valve mounted in
the pump discharge.
2.11.2 Tanks
Construct of high density polyethylene, cylindrical in shape, and with a hinged cover. The tank shall have sufficient
capacity to require recharging only once per 7 days during normal operation. Provide tank with a valved cold
water line and, if necessary, a valved hot water fill line with suitable air gap. Provide tank with device to
indicate quantity of solution in the tank. Provide electric mixing device with tank.
2.11.3 Valve Injection Assembly
Provide for each feed pump. Construct of bronze or material suitable for chemicals being used and install in
condenser water line common to all pumps. Injection fitting shall have male pipe threads. Each assembly shall
include a shut-off valve and a check valve installed close to condenser water line.
2.11.4 Bleed-off Solenoid Valve
Provide in bleed-off line. Valve shall normally be in closed position and be opened by a 120 volt waterproof
solenoid coil. Connect bleed-off line to condenser water line and include a gate valve ahead of solenoid valve.
Extend a discharge line from solenoid valve to sewer drain.
2.11.5 Water Meter
Provide with electric contacting register, and remote accumulative counter and installed in make-up water line
near cooling tower. Meter shall be standard standard product used in water treatment.
2.11.6 Timers
Shall be automatic reset, adjustable type, and electrically operated. House in metal NEMA type cabinet with a
hinged front. Timer shall be suitable for 120 volt current.
2.11.7 Conductivity Controller
Controller shall measure the total dissolved solids in system water by conductivity. The conductivity sensor
shall consist of epoxy insulated carbon electrodes and shall not require platinizing. Controller shall have
a meter with a visual readout, set point adjustment with a range between 200 micromhos/cm and 4000 micromhos/cm
and a red pilot light indicating water conductivity above set point. Unit shall operate from a 120 volt power
source.
2.11.8 Control Panel
Provide a factory-wired, NEMA 12, control panel for each system. Construct of steel with hinged door and lock,
and suitable for surface mounting. Pre-wire controls to numbered terminal strips. Provide laminated plastic
nameplates identifying the switch function. Include the following with the panel:
a. Main power switch and indicating lamp
b. MAN-OFF-AUTO selector switch
c. Indicating lamp for bleed-off valve
d. 120 Volt, heavy-duty, grounded duplex receptacle
e. Conductivity controller
f. Electric timer
g. Accumulative counter
2.11.9 Sequence of Operation
2.11.9.1 Conductivity Controller
Shall open the bleed-off solenoid valve when the conductivity of the cooling water rises above the set point
of the controller. When the conductivity falls below the set-point, the valve shall close.
2.11.9.2 Water Meter
Shall start the timer after a pre-set volume of make water has been measured.
2.11.9.3 Timer
Shall turn the feed pumps on for a pre-set amount of time.
2.11.10 Piping
Provide plastic piping and fittings conforming to ASTM D 2996 for water treatment system. Piping for feed pump
suction shall contain a foot valve and strainer.
2.11.11 Chemicals
NOTE: Select the applicable paragraphs from the following:
[Provide sufficient chemicals to initially place system in service and make tests.] [Provide same chemicals
used for treatment at station's other towers.]
2.11.11.1 Water Analysis
Description
Silica (Si02) ___________
Insoluble ___________
Iron and Aluminum Oxides ___________
Calcium (Ca) ___________
Magnesium (Mg) ___________
Sodium and Potassium (Na and K) ___________
Carbonate (C03) ___________
Bicarbonate (HC03) ___________
Sulfate (S04) ___________
Chloride (C1) ___________
Nitrate (N03) ___________
Turbidity ___________
pH ___________
Residual Chlorine ___________
Total Alkalinity ___________
Noncarbonate Hardness ___________
Total Hardness ___________
Dissolve Solids ___________
Fluorine ___________
[Furnish water analysis and provide sufficient chemicals to initially place system in service and make tests
prior to start up and acceptance by Government. [Provide same chemicals used for treatment at station's other
towers.]]
PART 3 EXECUTION
3.1 INSTALLATION
Installation procedures shall conform to ASHRAE 15 & 34 and the manufacturer's instructions. Set floor mounted
equipment on 150 mm 6 inches thick concrete housekeeping pads, complete with anchor bolts and grouting. Finish
housekeeping pads with two coats of oil-resistant epoxy polyamid coating. No drilling, cutting, burning, or
welding of structural parts of building will be permitted. Provide access panels for concealed valves, vent
controls, and control devices and items requiring periodic operation, inspection, or maintenance. Access panels
shall be of sufficient size and so located that concealed items may be serviced and maintained or removed and
replaced. Refrigerant safety relief devices shall have discharge piped to building exterior. Interlock compressor
operation with the water pump starters, so that the compressors cannot operate unless the pumps are operating.
3.2 MANUFACTURER'S FIELD SERVICES
Furnish manufacturer's representatives who are directly employed by the equipment manufacturers and trained to
perform the services specified. The manufacturers representatives shall furnish advice and services on the following
matters:
a. Erection, alignment, testing and dehydrating
b. Charging equipment with refrigerant and oil
c. Starting equipment and training Government personnel as to its proper care, operation, and
maintenance.
3.3 LOCATIONS AND CLEARANCES
Equipment shall be located so that working space is available for necessary servicing such as shaft removal,
disassembling compressor cylinders and pistons, replacing or adjusting drives, motors, or shaft seals, access
to water heads and valves of shell and tube equipment, tube cleaning or replacement, access to automatic controls,
refrigerant charging, lubrication, oil draining and working clearance under overhead lines.
3.4 IDENTIFICATION TAGS AND PLATES
Provide equipment with tags numbered and stamped for their use. Plates and tags shall be brass or nonferrous
material. Minimum letter and numeral sizes shall be 3.18 mm 1/8 inch high.
3.5 OPERATION AND MAINTENANCE MANUALS
Submit six copies of operating instructions outlining the step-by-step procedures required for system start-up,
operation and shutdown. The instructions shall include the manufacturer's name, model number, service manual,
parts list, and a brief description of equipment and their basic operating features. Submit 6 copies of maintenance
instructions listing routine maintenance procedures, possible breakdowns and repairs, and trouble shooting guides.
The instructions shall include simplified wiring diagrams. Framed instructions under glass or in laminated plastic,
including wiring and control diagrams showing the complete layout of the entire system, shall be posted where
directed. Condensed operating instructions explaining preventative maintenance procedures, methods of checking
the system for normal safe operation, and procedures for safely starting and stopping the system, shall be prepared
in typed form, framed as specified above for the wiring and control diagrams, and posted beside the diagrams.
Proposed diagrams, instructions, and other sheets, shall be submitted prior to posting. The framed instructions,
including wiring and control diagrams, shall be posted before acceptance testing of the systems.
3.6 INSTRUCTIONS TO GOVERNMENT PERSONNEL
Contractor shall conduct a training course for the operating staff as designated by the Contracting Officer.
The training period shall consist of a total [_____] hours of normal working time and shall start after the system
is functionally completed but prior to final acceptance tests. The field instructions shall cover the items
contained in the operating and maintenance instructions, as well as demonstrations of routine maintenance operations.
Notify the Contracting Officer at least 14 days prior to date of proposed conduction of the training course.
3.7 TESTS
Perform the tests and provide everything required. Notify the Contracting Officer, in writing, 10 days before
preforming tests. Tests shall be preformed in the presence of a manufacturer's representative.
3.7.1 Initial Start-Up and Operational Test
Provide chemicals and place water treatment systems in operation before initial start-up. Equipment shall be
started and operated. Follow the manufacturer's procedures and place the systems under all modes of operation.
Initial charges of lubricating oil shall be supplemented to assure maximum operating capacity. Safety and automatic
control instruments shall be adjusted. Record manufacturer's recommended readings hourly. Operational tests
shall cover a period of not less than [_____] days.
3.7.2 Test Reports
Submit the final test report for each system tested, describing test apparatus, instrumentation calculations,
and equipment data based on industry standard forms or reasonable facsimiles thereof. Data shall include: compressor
suction and discharge pressure; refrigerant charge pump, compressor and air moving device ampere readings; power
supply characteristics, including phase imbalance, with 1/2 percent accuracy; thermostatic expansion valve superheat-value
as determined by field test; subcooling; high and low refrigerant temperature switch set-points; low oil pressure
switch set-point; [defrost system timer and thermostat set-points; ] moisture content; ambient, condensing and
coolant temperatures; capacity control set-points; field data and adjustments which affect unit performance and
energy consumption. Where final adjustments and settings cannot be permanently marked or drilled and pinned
as an integral part of device, adjustment and setting data shall be included in test report.
3.8 WASTE MANAGEMENT
NOTE: Diverting waste from the landfill contributes to the following LEED credit:
MR2. Coordinate with Section 01572 CONSTRUCTION AND DEMOLITION WASTE MANAGEMENT.
Separate waste in accordance with the Waste Management Plan, placing copper materials, ferrous materials, and
galvanized sheet metal in designated areas for reuse. Close and seal tightly all partly used adhesives and solvents;
store protected in a well-ventilated, fire-safe area at moderate temperature.
3.9 SCHEDULE
Some metric measurements in this section are based on mathematical conversion of inch-pound measurements, and
not on metric measurements commonly agreed on by the manufacturers or other parties. The inch-pound and metric
measurements shown are as follows:
Products Inch-Pound Metric
a. Thermostat
Temp-Range = -30 to 50 degrees F = -34 to 10 degrees C
b. Motors
Capacity = 1/2 hp = 3/8 kW
= 10 hp = 7 1/2 kW
= 30 hp = 22 3/8 kW
= 3 hp = 2 1/4 kW