USACE / NAVFAC / AFCESA / NASA UFGS-23 23 00 (October 2007)
----------------------------
Preparing Activity: USACE Superseding
UFGS-23 23 00 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 23 23 00
REFRIGERANT PIPING
10/07
NOTE: This guide specification covers the requirements for refrigerant piping
systems inside of buildings, or leading from equipment adjacent to buildings.
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).
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 710(2004) Standard for Performance Rating of Liquid-Line DriersAHRI 720(2002) Refrigerant Access Valves and Hose ConnectorsAHRI 750(2007) Thermostatic Refrigerant Expansion ValvesAHRI 760(2007) Solenoid Valves for Use With Volatile Refrigerants][AMERICAN SOCIETY OF HEATING, REFRIGERATING AND AIR-CONDITIONING ENGINEERS (ASHRAE)ASHRAE 15 & 34WARNING: Text in tags exceeds the maximum length of 300 charactersASHRAE 17(2008) Method of Testing Capacity of Thermostatic Refrigerant Expansion Valves][AMERICAN WELDING SOCIETY (AWS)AWS A5.8/A5.8M(2004; Errata 2004) Specification for Filler Metals for Brazing and Braze WeldingAWS BRH(2007) Brazing HandbookAWS D1.1/D1.1M(2008) Structural Welding Code - SteelAWS Z49.1(2005) Safety in Welding, Cutting and Allied Processes][ASME INTERNATIONAL (ASME)ASME B1.20.1(1983; R 2006) Pipe Threads, General Purpose (Inch)ASME B16.11(2005) Forged Fittings, Socket-Welding and ThreadedASME B16.21(2005) Nonmetallic Flat Gaskets for Pipe FlangesASME B16.22(2001; R 2005) Standard for Wrought Copper and Copper Alloy Solder Joint Pressure FittingsASME B16.26(2006) Standard for Cast Copper Alloy Fittings for Flared Copper TubesASME B16.3(2006) Malleable Iron Threaded Fittings, Classes 150 and 300ASME B16.5(2003) Standard for Pipe Flanges and Flanged Fittings: NPS 1/2 Through NPS 24ASME B16.9(2007) Standard for Factory-Made Wrought Steel Buttwelding FittingsASME B31.1(2007; Addenda 2008) Power PipingASME B31.5(2006) Refrigeration Piping and Heat Transfer ComponentsASME B31.9(2008) Building Services PipingASME B40.100(2005) Pressure Gauges and Gauge AttachmentsASME BPVC SEC IX(2007; Addenda 2008) Boiler and Pressure Vessel Code; Section IX, Welding and Brazing Qualifications][ASTM INTERNATIONAL (ASTM)ASTM A 193/A 193M(2008b) Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for High-Temperature ServiceASTM A 334/A 334M(2004a) Standard Specification for Seamless and Welded Carbon and Alloy-Steel Tubes for Low-Temperature ServiceASTM A 53/A 53M(2007) Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and SeamlessASTM 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 B 280(2008) Standard Specification for Seamless Copper Tube for Air Conditioning and Refrigeration Field ServiceASTM B 32(2008) Standard Specification for Solder MetalASTM B 62(2002) Standard Specification for Composition Bronze or Ounce Metal CastingsASTM B 75(2002) Standard Specification for Seamless Copper TubeASTM B 75M(1999; R 2005) Standard Specification for Seamless Copper Tube (Metric)ASTM B 813(2000e1) Standard Specification for Liquid and Paste Fluxes for Soldering of Copper and Copper Alloy TubeASTM D 3308(2006) PTFE Resin Skived TapeASTM D 520(2000; R 2005) Zinc Dust PigmentASTM E 84(2008a) Standard Test Method for Surface Burning Characteristics of Building Materials][MANUFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTINGS INDUSTRY (MSS)MSS SP-58(2002) Standard for Pipe Hangers and Supports - Materials, Design and ManufactureMSS SP-69(2003; R 2004) Standard for Pipe Hangers and Supports - Selection and Application]1.2 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
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, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are for [Contractor Quality Control approval.][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 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Refrigerant Piping System[; G][; G, [_____]]
Drawings, at least [5 weeks] [_____] prior to beginning construction, provided in adequate
detail to demonstrate compliance with contract requirements. Drawings shall consist of:
a. Piping layouts which identify all valves and fittings.
b. Plans and elevations which identify clearances required for maintenance and operation.
SD-03 Product Data
Refrigerant Piping System
Manufacturer's standard catalog data, at least [5 weeks] [_____] prior to the purchase or
installation of a particular component, highlighted to show material, size, options, performance
charts and curves, etc. in adequate detail to demonstrate compliance with contract requirements.
Include in the data manufacturer's recommended installation instructions and procedures. Provide
data for the following components as a minimum:
a. Piping and Fittings
b. Valves
c. Piping Accessories
d. Pipe Hangers, Inserts, and Supports
Spare Parts
Spare parts data for each different item of equipment specified in Army projects only.
Qualifications[; G][; G, [_____]]
[_____] copies of qualified procedures, and list of names and identification symbols of qualified
welders and welding operators, prior to non-factory welding operations.
Refrigerant Piping Tests[; G][; G, [_____]]
A schedule, at least [2] [_____] weeks prior to the start of related testing, for each test.
Identify the proposed date, time, and location for each test.
Demonstrations[; G][; G, [_____]]
A schedule, at least [2] [_____] weeks prior to the date of the proposed training course,
which identifies the date, time, and location for the training.
Verification of Dimensions
A letter, at least [2] [_____] weeks prior to beginning construction, including the date the
site was visited, conformation of existing conditions, and any discrepancies found.
SD-06 Test Reports
Refrigerant Piping Tests
[Six] [_____] copies of the report in bound 216 by 279 mm 8 1/2 by 11 inch booklets documenting
all phases of the tests performed. The report shall include initial test summaries, all repairs/adjustments
made, and the final test results.
SD-07 Certificates
Service Organization[; G][; G, [_____]]
A certified list of qualified permanent service organizations for support of the equipment
which includes their addresses and qualifications. The service organizations shall be reasonably
convenient to the equipment installation and be able to render satisfactory service to the equipment
on a regular and emergency basis during the warranty period of the contract.
SD-10 Operation and Maintenance Data
Maintenance
Operation and Maintenance Manuals
Data Package 2 in accordance with Section 01 78 23 OPERATION AND MAINTENANCE DATA.
[Six] [_____] complete copies of an operation manual in bound 216 by 279 8 1/2 by 11 inch
booklets listing step-by-step procedures required for system startup, operation, abnormal shutdown,
emergency shutdown, and normal shutdown at least [4] [_____] weeks prior to the first training
course. The booklets shall include the manufacturer's name, model number, and parts list.
The manuals shall include the manufacturer's name, model number, service manual, and a brief
description of all equipment and their basic operating features.
[Six] [_____] complete copies of maintenance manual in bound 216 by 279 8 1/2 x 11 inch booklets
listing routine maintenance procedures, possible breakdowns and repairs, and a trouble shooting
guide. The manuals shall include piping layouts and simplified wiring and control diagrams
of the system as installed.
1.3 QUALITY ASSURANCE
1.3.1 Qualifications
NOTE: If the need exists for more stringent requirements for weldments, delete
the first bracketed statement, otherwise delete the second. Regarding welding
Section reference, use first bracketed statement for Army projects and delete
the second option of the Navy Section; and vice versa.
[Piping shall be welded in accordance with the 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 to 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. Structural members shall be welded in accordance with Section [05 05 23 WELDING, STRUCTURAL]
[05 12 00 STRUCTURAL STEEL].] [Welding and nondestructive testing procedures are specified in Section [
43 02 00 WELDING PRESSURE PIPING] [40 17 26.00 20 WELDING PRESSURE PIPING].]
1.3.2 Contract Drawings
Because of the small scale of the drawings, it is not possible to indicate all offsets, fittings, and accessories
that may be required. Carefully investigate the plumbing, fire protection, electrical, structural and finish
conditions that would affect the work to be performed and arrange such work accordingly, furnishing required
offsets, fittings, and accessories to meet such conditions.
1.4 DELIVERY, STORAGE, AND HANDLING
Protect stored items from the weather, humidity and temperature variations, dirt and dust, or other contaminants.
Proper protection and care of all material both before and during installation is the Contractor's responsibility.
Replace any materials found to be damaged at the Contractor's expense. During installation, cap piping and similar
openings to keep out dirt and other foreign matter.
1.5 MAINTENANCE
1.5.1 General
Operation and maintenance data shall comply with the requirements of Section 01 78 23 OPERATION AND MAINTENANCE
DATA and as specified herein.
1.5.2 Extra Materials
NOTE: Remove this paragraph in Navy projects.
Submit spare parts data for each different item of equipment specified, after approval of detail drawings and
not later than [_____] months prior to the date of beneficial occupancy. The data shall include a complete list
of parts and supplies, with current unit prices and source of supply, a recommended spare parts list for 1 year
of operation, and a list of the parts recommended by the manufacturer to be replaced on a routine basis.
PART 2 PRODUCTS
2.1 STANDARD COMMERCIAL PRODUCTS
a. Provide materials and equipment which are standard products of a manufacturer regularly engaged in
the manufacturing of such products, that are of a similar material, design and workmanship and that have
been in satisfactory commercial or industrial use for 2 years prior to bid opening.
b. The 2 year use shall include applications of equipment and materials under similar circumstances
and of similar size. The 2 years experience shall be satisfactorily completed by a product which has
been sold or is offered for sale on the commercial market through advertisements, manufacturer's catalogs,
or brochures. Products having less than a 2 year field service record will be acceptable if a certified
record of satisfactory field operation, for not less than 6000 hours exclusive of the manufacturer's
factory tests, can be shown.
c. Products shall be supported by a service organization. System components shall be environmentally
suitable for the indicated locations.
d. Exposed equipment moving parts, parts that produce high operating temperature, parts which may be
electrically energized, and parts that may be a hazard to operating personnel shall be insulated, fully
enclosed, guarded, or fitted with other types of safety devices. Install safety devices so that proper
operation of equipment is not impaired. Welding and cutting safety requirements shall be in accordance
with AWS Z49.1.
2.2 ELECTRICAL WORK
NOTE: Use the first bracketed statement for Army projects or the second for
Navy jobs; delete the non-applicable statement.
[Electrical equipment and wiring shall be in accordance with Section 26 20 00 INTERIOR DISTRIBUTION SYSTEM.
Field wiring shall be in accordance with manufacturer's instructions.] [Manual or automatic control and protective
or signal devices required for the operation specified and any control wiring required for controls and devices
specified, but not shown, shall be provided.]
2.3 REFRIGERANT PIPING SYSTEM
NOTE: This specification is written primarily for Group A1 refrigerants (i.e.,
R-11, R-12, R-22, and R-134a). For information on refrigerant classifications
refer to ASHRAE 15 & 34. If the piping system is intended for other refrigerants
such as R-123 (Group B1) or ammonia (Group B2), then the designer will have
to research ASHRAE 15 & 34 and ASME B31.5 and modify the specification appropriately.
Refrigerant piping, valves, fittings, and accessories shall be in accordance with ASHRAE 15 & 34 and ASME B31.5
, except as specified herein. Refrigerant piping, valves, fittings, and accessories shall be compatible with
the fluids used and capable of withstanding the pressures and temperatures of the service. Refrigerant piping,
valves, and accessories used for refrigerant service shall be cleaned, dehydrated, and sealed (capped or plugged)
prior to shipment from the manufacturer's plant.
2.4 PIPE, FITTINGS AND END CONNECTIONS (JOINTS)
2.4.1 Steel Pipe
Steel pipe for refrigerant service shall conform to ASTM A 53/A 53M, Schedule 40, Type E or S, Grades A or B.
Type F pipe shall not be used.
2.4.1.1 Welded Fittings and Connections
Butt-welded fittings shall conform to ASME B16.9. Socket-welded fittings shall conform to ASME B16.11. Welded
fittings shall be identified with the appropriate grade and marking symbol. Welded valves and pipe connections
(both butt-welds and socket-welds types) shall conform to ASME B31.9.
2.4.1.2 Threaded Fittings and Connections
Threaded fitting shall conform to ASME B16.3. Threaded valves and pipe connections shall conform to ASME B1.20.1
.
2.4.1.3 Flanged Fittings and Connections
Flanges shall conform to ASME B16.5, Class 150. Gaskets shall be nonasbestos compressed material in accordance
with ASME B16.21, 1.59 mm 1/16 inch thickness, full face or self-centering flat ring type. This gaskets shall
contain aramid fibers bonded with styrene butadeine rubber (SBR) or nitrile butadeine rubber (NBR). Bolts, nuts,
and bolt patterns shall conform to ASME B16.5. Bolts shall be high or intermediate strength material conforming
to ASTM A 193/A 193M.
2.4.2 Steel Tubing
Tubing shall be cold-rolled, electric-forged, welded-steel in accordance with ASTM A 334/A 334M, Grade 1. Joints
and fittings shall be socket type provided by the steel tubing manufacturer.
2.4.3 Copper Tubing
Copper tubing shall conform to ASTM B 280 annealed or hard drawn as required. Copper tubing shall be soft annealed
where bending is required and hard drawn where no bending is required. Soft annealed copper tubing shall not
be used in sizes larger than 35 mm 1-3/8 inches. Joints shall be brazed except that joints on lines 22 mm 7/8
inchand smaller may be flared. Cast copper alloy fittings for flared copper tube shall conform to ASME B16.26
and ASTM B 62. Wrought copper and bronze solder-joint pressure fittings shall conform to ASME B16.22 and ASTM B 75M
ASTM B 75. Joints and fittings for brazed joint shall be wrought-copper or forged-brass sweat fittings. Cast
sweat-type joints and fittings shall not be allowed for brazed joints. Brass or bronze adapters for brazed tubing
may be used for connecting tubing to flanges and to threaded ends of valves and equipment.
2.4.4 Solder
Solder shall conform to ASTM B 32, grade Sb5, tin-antimony alloy for service pressures up to 1034 kPa 150 psig
. Solder flux shall be liquid or paste form, non-corrosive and conform to ASTM B 813.
2.4.5 Brazing Filler Metal
Filler metal shall conform to AWS A5.8/A5.8M, Type BAg-5 with AWS Type 3 flux, except Type BCuP-5 or BCuP-6 may
be used for brazing copper-to-copper joints.
2.5 VALVES
Valves shall be designed, manufactured, and tested specifically for refrigerant service. Valve bodies shall
be of brass, bronze, steel, or ductile iron construction. Valves 25 mm 1 inch and smaller shall have brazed
or socket welded connections. Valves larger than 25 mm 1 inch shall have [tongue-and-groove flanged] [butt welded]
end connections. Threaded end connections shall not be used, except in pilot pressure or gauge lines where maintenance
disassembly is required and welded flanges cannot be used. Internal parts shall be removable for inspection
or replacement without applying heat or breaking pipe connections. Valve stems exposed to the atmosphere shall
be stainless steel or corrosion resistant metal plated carbon steel. Direction of flow shall be legibly and
permanently indicated on the valve body. Control valve inlets shall be fitted with integral or adapted strainer
or filter where recommended or required by the manufacturer. Purge, charge and receiver valves shall be of manufacturer's
standard configuration.
2.5.1 Refrigerant Stop Valves
Valve shall be the globe or full-port ball type with a back-seating stem especially packed for refrigerant service.
Valve packing shall be replaceable under line pressure. Valve shall be provided with a [handwheel] [or] [wrench]
operator and a seal cap. Valve shall be the straight or angle pattern design as indicated.
2.5.2 Check Valves
Valve shall be the swing or lift type as required to provide positive shutoff at the differential pressure indicated.
Valve shall be provide with resilient seat.
2.5.3 Liquid Solenoid Valves
Valves shall comply with AHRI 760 and be suitable for continuous duty with applied voltages 15 percent under
and 5 percent over nominal rated voltage at maximum and minimum encountered pressure and temperature service
conditions. Valves shall be direct-acting or pilot-operating type, packless, except that packed stem, seal capped,
manual lifting provisions shall be furnished. Solenoid coils shall be moisture-proof, UL approved, totally encapsulated
or encapsulated and metal jacketed as required. Valves shall have safe working pressure of 2760 kPa 400 psi
and a maximum operating pressure differential of at least 1375 kPa 200 psi at 85 percent rated voltage. Valves
shall have an operating pressure differential suitable for the refrigerant used.
2.5.4 Expansion Valves
Valve shall conform to AHRI 750 and ASHRAE 17. Valve shall be the diaphragm and spring-loaded type with internal
or external equalizers, and bulb and capillary tubing. Valve shall be provided with an external superheat adjustment
along with a seal cap. Internal equalizers may be utilized where flowing refrigerant pressure drop between outlet
of the valve and inlet to the evaporator coil is negligible and pressure drop across the evaporator is less than
the pressure difference corresponding to 1 degree C 2 degrees F of saturated suction temperature at evaporator
conditions. Bulb charge shall be determined by the manufacturer for the application and such that liquid will
remain in the bulb at all operating conditions. Gas limited liquid charged valves and other valve devices for
limiting evaporator pressure shall not be used without a distributor or discharge tube or effective means to
prevent loss of control when bulb becomes warmer than valve body. Pilot-operated valves shall have a characterized
plug to provide required modulating control. A de-energized solenoid valve may be used in the pilot line to
close the main valve in lieu of a solenoid valve in the main liquid line. An isolatable pressure gauge shall
be provided in the pilot line, at the main valve. Automatic pressure reducing or constant pressure regulating
expansion valves may be used only where indicted or for constant evaporator loads.
2.5.5 Safety Relief Valves
Valve shall be the two-way type, unless indicated otherwise. Valve shall bear the ASME code symbol. Valve capacity
shall be certified by the National Board of Boiler and Pressure Vessel Inspectors. Valve shall be of an automatically
reseating design after activation.
2.5.6 Evaporator Pressure Regulators, Direct-Acting
Valve shall include a diaphragm/spring assembly, external pressure adjustment with seal cap, and pressure gauge
port. Valve shall maintain a constant inlet pressure by balancing inlet pressure on diaphragm against an adjustable
spring load. Pressure drop at system design load shall not exceed the pressure difference corresponding to a
1 degree C 2 degrees F change in saturated refrigerant temperature at evaporator operating suction temperature.
Spring shall be selected for indicated maximum allowable suction pressure range.
2.5.7 Refrigerant Access Valves
Refrigerant access valves and hose connections shall be in accordance with AHRI 720.
2.6 PIPING ACCESSORIES
2.6.1 Filter Driers
Driers shall conform to AHRI 710. Sizes 15 mm 5/8 inch and larger shall be the full flow, replaceable core type.
Sizes 13 mm 1/2 inch and smaller shall be the sealed type. Cores shall be of suitable desiccant that will not
plug, cake, dust, channel, or break down, and shall remove water, acid, and foreign material from the refrigerant.
Filter driers shall be constructed so that none of the desiccant will pass into the refrigerant lines. Minimum
bursting pressure shall be 10.3 MPa 1,500 psi.
2.6.2 Sight Glass and Liquid Level Indicator
2.6.2.1 Assembly and Components
Assembly shall be pressure- and temperature-rated and constructed of materials suitable for the service. Glass
shall be borosilicate type. Ferrous components subject to condensation shall be electro-galvanized.
2.6.2.2 Gauge Glass
Gauge glass shall include top and bottom isolation valves fitted with automatic checks, and packing followers;
red-line or green-line gauge glass; elastomer or polymer packing to suit the service; and gauge glass guard.
2.6.2.3 Bull's-Eye and Inline Sight Glass Reflex Lens
Bull's-eye and inline sight glass reflex lens shall be provided for dead-end liquid service. For pipe line mounting,
two plain lenses in one body suitable for backlighted viewing shall be provided.
2.6.2.4 Moisture Indicator
Indicator shall be a self-reversible action, moisture reactive, color changing media. Indicator shall be furnished
with full-color-printing tag containing color, moisture and temperature criteria. Unless otherwise indicated,
the moisture indicator shall be an integral part of each corresponding sight glass.
2.6.3 Vibration Dampeners
Dampeners shall be of the all-metallic bellows and woven-wire type.
2.6.4 Flexible Pipe Connectors
Connector shall be a composite of interior corrugated phosphor bronze or Type 300 Series stainless steel, as
required for fluid service, with exterior reinforcement of bronze, stainless steel or monel wire braid. Assembly
shall be constructed with a safety factor of not less than 4 at 150 degrees C300 degrees F. Unless otherwise
indicated, the length of a flexible connector shall be as recommended by the manufacturer for the service intended.
2.6.5 Strainers
Strainers used in refrigerant service shall have brass or cast iron body, Y-or angle-pattern, cleanable, not
less than 60-mesh noncorroding screen of an area to provide net free area not less than ten times the pipe diameter
with pressure rating compatible with the refrigerant service. Screens shall be stainless steel or monel and
reinforced spring-loaded where necessary for bypass-proof construction.
2.6.6 Pressure and Vacuum Gauges
Gauges shall conform to ASME B40.100 and shall be provided with throttling type needle valve or a pulsation dampener
and shut-off valve. Gauge shall be a minimum of 85 mm 3-1/2 inches in diameter with a range from 0 kPa 0 psig
to approximately 1.5 times the maximum system working pressure. Each gauge range shall be selected so that
at normal operating pressure, the needle is within the middle-third of the range.
2.6.7 Temperature Gauges
Temperature gauges shall be the industrial duty type and be provided for the required temperature range. Gauges
shall have Celsius scale in 1 degree Fahrenheit scale in 2 degrees graduations scale (black numbers) on a white
face. The pointer shall be adjustable. Rigid stem type temperature gauges shall be provided in thermal wells
located within 1.5 m 5 feet of the finished floor. Universal adjustable angle type or remote element type temperature
gauges shall be provided in thermal wells located 1.5 to 2.1 m 5 to 7 feet above the finished floor. Remote
element type temperature gauges shall be provided in thermal wells located 2.1 m 7 feet above the finished floor.
2.6.7.1 Stem Cased-Glass
Stem cased-glass case shall be polished stainless steel or cast aluminum, 229 mm 9 inches long, with clear acrylic
lens, and non-mercury filled glass tube with indicating-fluid column.
2.6.7.2 Bimetallic Dial
Bimetallic dial type case shall be not less than 89 mm 3-1/2 inches, stainless steel, and shall be hermetically
sealed with clear acrylic lens. Bimetallic element shall be silicone dampened and unit fitted with external
calibrator adjustment. Accuracy shall be one percent of dial range.
2.6.7.3 Liquid-, Solid-, and Vapor-Filled Dial
Liquid-, solid-, and vapor-filled dial type cases shall be not less than 89 mm 3-1/2 inches, stainless steel
or cast aluminum with clear acrylic lens. Fill shall be nonmercury, suitable for encountered cross-ambients,
and connecting capillary tubing shall be double-braided bronze.
2.6.7.4 Thermal Well
Thermal well shall be identical size, 13 or 19 mm 1/2 or 3/4 inch NPT connection, brass or stainless steel.
Where test wells are indicated, provide captive plug-fitted type 13 mm 1/2 inch NPT connection suitable for use
with either engraved stem or standard separable socket thermometer or thermostat. Mercury shall not be used
in thermometers. Extended neck thermal wells shall be of sufficient length to clear insulation thickness by
25 mm 1 inch.
2.6.8 Pipe Hangers, Inserts, and Supports
Pipe hangers, inserts, guides, and supports shall conform to MSS SP-58 and MSS SP-69.
2.6.9 Escutcheons
Escutcheons shall be chromium-plated iron or chromium-plated brass, either one piece or split pattern, held in
place by internal spring tension or set screws.
2.7 FABRICATION
2.7.1 Factory Coating
NOTE: For equipment to be installed outdoors, adequate protection will be specified.
Manufacturers must submit evidence that unit specimen have passed the specified
salt spray fog test. A 125 hour test will be specified in a noncorrosive environment
and a 500 hour test will be specified in a corrosive environment.
Unless otherwise specified, 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 shall have weather
resistant finishes that will withstand [125] [500] hours exposure to the salt spray test specified in ASTM B 117
using a 5 percent sodium chloride solution. Immediately after completion of the test, the specimen shall show
no signs of blistering, wrinkling, cracking, or loss of adhesion and no sign of rust creepage beyond 3 mm 1/8
inch on either side of the scratch mark. Cut edges of galvanized surfaces where hot-dip galvanized sheet steel
is used shall be coated with a zinc-rich coating conforming to ASTM D 520, Type I.
2.7.2 Factory Applied Insulation
[Refrigerant suction lines between the cooler and each compressor [and cold gas inlet connections to gas cooled
motors]] [Refrigerant pumps and exposed chilled water lines on absorption chillers] shall be insulated with not
less than 19 mm 3/4 inch thick unicellular plastic foam. Factory insulated items installed outdoors are not
required to be fire-rated. As a minimum, factory insulated items installed indoors shall have a flame spread
index no higher than 75 and a smoke developed index no higher than 150. Factory insulated items (no jacket)
installed indoors and which are located in air plenums, in ceiling spaces, and in attic spaces shall have a flame
spread index no higher than 25 and a smoke developed index no higher than 50. Flame spread and smoke developed
indexes shall be determined by ASTM E 84. Insulation shall be tested in the same density and installed thickness
as the material to be used in the actual construction. Material supplied by a manufacturer with a jacket shall
be tested as a composite material. Jackets, facings, and adhesives shall have a flame spread index no higher
than 25 and a smoke developed index no higher than 50 when tested in accordance with ASTM E 84.
PART 3 EXECUTION
3.1 EXAMINATION
After becoming familiar with all details of the work, perform a verification of dimensions in the field, and
advise the Contracting Officer of any discrepancy before performing any work.
3.2 INSTALLATION
NOTE: Belowground refrigerant piping should be avoided if at all possible.
Direct buried refrigerant piping will not be installed under any circumstances.
In the event that belowground pipe routing is the only alternative, the piping
will be routed through an accessible trench system (i.e. concrete, fiberglass,
PVC, etc). The designer will specifically detail the trench design as well
as fully detail the piping techniques necessary to accommodate oil circulation
at both full and part load conditions. Oil circulation is extremely critical
to the successful operation of any refrigerant system. Designers will avoid
creating any oil traps within a refrigerant piping system.
Pipe and fitting installation shall conform to the requirements of ASME B31.1. Pipe shall be cut accurately
to measurements established at the jobsite, and worked into place without springing or forcing, completely clearing
all windows, doors, and other openings. Cutting or other weakening of the building structure to facilitate piping
installation will not be permitted without written approval. Pipe or tubing shall be cut square, shall have
burrs removed by reaming, and shall permit free expansion and contraction without causing damage to the building
structure, pipe, joints, or hangers.
3.2.1 Directional Changes
Changes in direction shall be made with fittings, except that bending of pipe 100 mm 4 inches and smaller will
be permitted, provided a pipe bender is used and wide weep bends are formed. Mitering or notching pipe or other
similar construction to form elbows or tees will not be permitted. The centerline radius of bends shall not
be less than 6 diameters of the pipe. Bent pipe showing kinks, wrinkles, flattening, or other malformations
will not be accepted.
3.2.2 Functional Requirements
Piping shall be installed 4 mm/m 1/2 inch/10 feet of pipe in the direction of flow to ensure adequate oil drainage.
Open ends of refrigerant lines or equipment shall be properly capped or plugged during installation to keep moisture,
dirt, or other foreign material out of the system. Piping shall remain capped until installation. Equipment
piping shall be in accordance with the equipment manufacturer's recommendations and the contract drawings. Equipment
and piping arrangements shall fit into space allotted and allow adequate acceptable clearances for installation,
replacement, entry, servicing, and maintenance.
3.2.3 Fittings and End Connections
3.2.3.1 Threaded Connections
Threaded connections shall be made with tapered threads and made tight with PTFE tape complying with ASTM D 3308
or equivalent thread-joint compound applied to the male threads only. Not more than three threads shall show
after the joint is made.
3.2.3.2 Brazed Connections
Brazing shall be performed in accordance with AWS BRH, except as modified herein. During brazing, the pipe and
fittings shall be filled with a pressure regulated inert gas, such as nitrogen, to prevent the formation of scale.
Before brazing copper joints, both the outside of the tube and the inside of the fitting shall be cleaned with
a wire fitting brush until the entire joint surface is bright and clean. Brazing flux shall not be used. Surplus
brazing material shall be removed at all joints. Steel tubing joints shall be made in accordance with the manufacturer's
recommendations. Joints in steel tubing shall be painted with the same material as the baked-on coating within
8 hours after joints are made. Tubing shall be protected against oxidation during brazing by continuous purging
of the inside of the piping using nitrogen. Piping shall be supported prior to brazing and not be sprung or
forced.
3.2.3.3 Welded Connections
Welded joints in steel refrigerant piping shall be fusion-welded. Branch connections shall be made with welding
tees or forged welding branch outlets. Pipe shall be thoroughly cleaned of all scale and foreign matter before
the piping is assembled. During welding the pipe and fittings shall be filled with an inert gas, such as nitrogen,
to prevent the formation of scale. Beveling, alignment, heat treatment, and inspection of weld shall conform
to ASME B31.1. Weld defects shall be removed and rewelded at no additional cost to the Government. Electrodes
shall be stored and dried in accordance with AWS D1.1/D1.1M or as recommended by the manufacturer. Electrodes
that have been wetted or that have lost any of their coating shall not be used.
3.2.3.4 Flared Connections
When flared connections are used, a suitable lubricant shall be used between the back of the flare and the nut
in order to avoid tearing the flare while tightening the nut.
3.2.3.5 Flanged Connections
When steel refrigerant piping is used, union or flange joints shall be provided in each line immediately preceding
the connection to each piece of equipment requiring maintenance, such as compressors, coils, chillers, control
valves, and other similar items. Flanged joints shall be assembled square end tight with matched flanges, gaskets,
and bolts. Gaskets shall be suitable for use with the refrigerants to be handled.
3.2.4 Valves
3.2.4.1 General
Refrigerant stop valves shall be installed on each side of each piece of equipment such as compressors condensers,
evaporators, receivers, and other similar items in multiple-unit installation, to provide partial system isolation
as required for maintenance or repair. Stop valves shall be installed with stems horizontal unless otherwise
indicated. Ball valves shall be installed with stems positioned to facilitate operation and maintenance. Isolating
valves for pressure gauges and switches shall be external to thermal insulation. Safety switches shall not be
fitted with isolation valves. Filter dryers having access ports may be considered a point of isolation. Purge
valves shall be provided at all points of systems where accumulated noncondensible gases would prevent proper
system operation. Valves shall be furnished to match line size, unless otherwise indicated or approved.
3.2.4.2 Expansion Valves
Expansion valves shall be installed with the thermostatic expansion valve bulb located on top of the suction
line when the suction line is less than 54 mm 2-1/8 inches in diameter and at the 4 o'clock or 8 o'clock position
on lines larger than 54 mm 2-1/8 inches. The bulb shall be securely fastened with two clamps. The bulb shall
be insulated. The bulb shall installed in a horizontal portion of the suction line, if possible, with the pigtail
on the bottom. If the bulb must be installed in a vertical line, the bulb tubing shall be facing up.
3.2.4.3 Valve Identification
NOTE: Delete last two sentences when identification tags are not considered
necessary in small projects.
Each system valve, including those which are part of a factory assembly, shall be tagged. Tags shall be in alphanumeric
sequence, progressing in direction of fluid flow. Tags shall be embossed, engraved, or stamped plastic or nonferrous
metal of various shapes, sized approximately 34 mm 1-3/8 inch diameter, or equivalent dimension, substantially
attached to a component or immediately adjacent thereto. Tags shall be attached with nonferrous, heavy duty,
bead or link chain, 14 gauge 14 gauge annealed wire, nylon cable bands or as approved. Tag numbers shall be
referenced in Operation and Maintenance Manuals and system diagrams.
3.2.5 Vibration Dampers
Vibration damper shall be provided in the suction and discharge lines on spring mounted compressors. Vibration
dampers shall be installed parallel with the shaft of the compressor and shall be anchored firmly at the upstream
end on the suction line and the downstream end in the discharge line.
3.2.6 Strainers
Strainers shall be provided immediately ahead of solenoid valves and expansion devices. Strainers may be an
integral part of an expansion valve.
3.2.7 Filter Dryer
A liquid line filter dryer shall be provided on each refrigerant circuit located such that all liquid refrigerant
passes through a filter dryer. Dryers shall be sized in accordance with the manufacturer's recommendations for
the system in which it is installed. Dryers shall be installed such that it can be isolated from the system,
the isolated portion of the system evacuated, and the filter dryer replaced. Dryers shall be installed in the
horizontal position except replaceable core filter dryers may be installed in the vertical position with the
access flange on the bottom.
3.2.8 Sight Glass
A moisture indicating sight glass shall be installed in all refrigerant circuits down stream of all filter dryers
and where indicated. Site glasses shall be full line size.
3.2.9 Discharge Line Oil Separator
Discharge line oil separator shall be provided in the discharge line from each compressor. Oil return line shall
be connected to the compressor as recommended by the compressor manufacturer.
3.2.10 Accumulator
NOTE: Suction line accumulator should be included under certain split system
applications, such as having extended refrigerant lines, 15 m (50 feet) or longer.
If accumulator is not used then delete this paragraph.
Accumulators shall be provided in the suction line to each compressor.
3.2.11 Flexible Pipe Connectors
Connectors shall be installed perpendicular to line of motion being isolated. Piping for equipment with bidirectional
motion shall be fitted with two flexible connectors, in perpendicular planes. Reinforced elastomer flexible
connectors shall be installed in accordance with manufacturer's instructions. Piping guides and restraints related
to flexible connectors shall be provided as required.
3.2.12 Temperature Gauges
Temperature gauges shall be located specifically on, but not limited to the following: [the sensing element
of each automatic temperature control device where a thermometer is not an integral part thereof] [the liquid
line leaving a receiver] [and] [the suction line at each evaporator or liquid cooler]. Thermal wells for insertion
thermometers and thermostats shall extend beyond thermal insulation surface not less than 25 mm 1 inch.
3.2.13 Pipe Hangers, Inserts, and Supports
Pipe hangers, inserts, and supports shall conform to MSS SP-58 and MSS SP-69, except as modified herein. Pipe
hanger types 5, 12, and 26 shall not be used. Hangers used to support piping 50 mm 2 inches and larger shall
be fabricated to permit adequate adjustment after erection while still supporting the load. Piping subjected
to vertical movement, when operating temperatures exceed ambient temperatures, shall be supported by variable
spring hangers and supports or by constant support hangers.
3.2.13.1 Hangers
Type 3 shall not be used on insulated piping. Type 24 may be used only on trapeze hanger systems or on fabricated
frames.
3.2.13.2 Inserts
Type 18 inserts shall be secured to concrete forms before concrete is placed. Continuous inserts which allow
more adjustments may be used if they otherwise meet the requirements for Type 18 inserts.
3.2.13.3 C-Clamps
Type 19 and 23 C-clamps shall be torqued in accordance with MSS SP-69 and have both locknuts and retaining devices,
furnished by the manufacturer. Field-fabricated C-clamp bodies or retaining devices are not acceptable.
3.2.13.4 Angle Attachments
Type 20 attachments used on angles and channels shall be furnished with an added malleable-iron heel plate or
adapter.
3.2.13.5 Saddles and Shields
Where Type 39 saddle or Type 40 shield are permitted for a particular pipe attachment application, the Type 39
saddle, connected to the pipe, shall be used on all pipe 100 mm 4 inches and larger when the temperature of the
medium is 16 degrees C 60 degrees F or higher. Type 40 shields shall be used on all piping less than 100 mm
4 inches and all piping 100 mm 4 inches and larger carrying medium less than 16 degrees C 60 degrees F. A high
density insulation insert of cellular glass shall be used under the Type 40 shield for piping 50 mm 2 inches
and larger.
3.2.13.6 Horizontal Pipe Supports
Horizontal pipe supports shall be spaced as specified in MSS SP-69 and a support shall be installed not over
300 mm 1 foot from the pipe fitting joint at each change in direction of the piping. Pipe supports shall be
spaced not over 1.5 m 5 feet apart at valves. [Pipe hanger loads suspended from steel joist with hanger loads
between panel points in excess of 23 kg 50 pounds shall have the excess hanger loads suspended from panel points.]
3.2.13.7 Vertical Pipe Supports
Vertical pipe shall be supported at each floor, except at slab-on-grade, and at intervals of not more than 4.5
m 15 feet not more than 2.4 m 8 feet from end of risers, and at vent terminations.
3.2.13.8 Pipe Guides
Type 35 guides using, steel, reinforced polytetrafluoroethylene (PTFE) or graphite slides shall be provided where
required to allow longitudinal pipe movement. Lateral restraints shall be provided as required. Slide materials
shall be suitable for the system operating temperatures, atmospheric conditions, and bearing loads encountered.
3.2.13.9 Steel Slides
Where steel slides do not require provisions for restraint of lateral movement, an alternate guide method may
be used. On piping 100 mm 4 inches and larger, a Type 39 saddle shall be used. On piping under 100 mm 4 inches
, a Type 40 protection shield may be attached to the pipe or insulation and freely rest on a steel slide plate.
3.2.13.10 High Temperature Guides with Cradles
Where there are high system temperatures and welding to piping is not desirable, then the Type 35 guide shall
include a pipe cradle, welded to the guide structure and strapped securely to the pipe. The pipe shall be separated
from the slide material by at least 100 mm 4 inches, or by an amount adequate for the insulation, whichever is
greater.
3.2.13.11 Multiple Pipe Runs
In the support of multiple pipe runs on a common base member, a clip or clamp shall be used where each pipe crosses
the base support member. Spacing of the base support members shall not exceed the hanger and support spacing
required for an individual pipe in the multiple pipe run.
3.2.13.12 Seismic Requirements
NOTE: Provide seismic details, if a Government designer (either Corps office
of A/E) is the Engineer of Record, and show on the drawings. Delete the bracketed
phrase "as shown on the drawings" if no seismic details are provided. UFC 3-310-04
SEISMIC DESIGN FOR BUILDINGS and Sections 13 48 00 SEISMIC PROTECTION FOR MISCELLANEOUS
EQUIPMENT and 13 48 00.00 10 SEISMIC PROTECTION FOR MECHANICAL EQUIPMENT or
22 05 48.00 20 MECHANICAL SOUND, VIBRATION, AND SEISMIC CONTROL properly edited,
must be included in the contract documents.
Piping and attached valves shall be supported and braced to resist seismic loads as specified under UFC 3-310-04
and Sections 13 48 00 SEISMIC PROTECTION FOR MILCELLANEOUS EQUIPMENT and [13 48 00.00 10 SEISMIC PROTECTION FOR
MECHANICAL EQUIPMENT] [22 05 48.00 20 MECHANICAL SOUND, VIBRATION, AND SEISMIC CONTROL] [as shown on the drawings].
Structural steel required for reinforcement to properly support piping, headers, and equipment but not shown
shall be provided under this section. Material used for support shall be as specified under Section
05 12 00 STRUCTURAL STEEL.
3.2.13.13 Structural Attachments
Attachment to building structure concrete and masonry shall be by cast-in concrete inserts, built-in anchors,
or masonry anchor devices. Inserts and anchors shall be applied with a safety factor not less than 5. Supports
shall not be attached to metal decking. Masonry anchors for overhead applications shall be constructed of ferrous
materials only. Structural steel brackets required to support piping, headers, and equipment, but not shown,
shall be provided under this section. Material used for support shall be as specified under Section
05 12 00 STRUCTURAL STEEL.
3.2.14 Pipe Alignment Guides
Pipe alignment guides shall be provided where indicated for expansion loops, offsets, and bends and as recommended
by the manufacturer for expansion joints, not to exceed 1.5 m 5 feet on each side of each expansion joint, and
in lines 100 mm 4 inches or smaller not more than 600 mm 2 feet on each side of the joint.
3.2.15 Pipe Anchors
Anchors shall be provided wherever necessary or indicated to localize expansion or to prevent undue strain on
piping. Anchors shall consist of heavy steel collars with lugs and bolts for clamping and attaching anchor braces,
unless otherwise indicated. Anchor braces shall be installed in the most effective manner to secure the desired
results using turnbuckles where required. Supports, anchors, or stays shall not be attached where they will
injure the structure or adjacent construction during installation or by the weight of expansion of the pipeline.
Where pipe and conduit penetrations of vapor barrier sealed surfaces occur, these items shall be anchored immediately
adjacent to each penetrated surface, to provide essentially zero movement within penetration seal. Detailed
drawings of pipe anchors shall be submitted for approval before installation.
3.2.16 Building Surface Penetrations
Sleeves shall not be installed in structural members except where indicated or approved. Sleeves in nonload
bearing surfaces shall be galvanized sheet metal, conforming to ASTM A 653/A 653M, Coating Class G-90, 1.0 mm
(20 gauge) 20 gauge. Sleeves in load bearing surfaces shall be uncoated carbon steel pipe, conforming to ASTM A 53/A 53M
, [Schedule 30] [Schedule 20] [Standard weight]. Sealants shall be applied to moisture and oil-free surfaces
and elastomers to not less than 13 mm 1/2 inch depth. Sleeves shall not be installed in structural members.
3.2.16.1 Refrigerated Space
Refrigerated space building surface penetrations shall be fitted with sleeves fabricated from hand-lay-up or
helically wound, fibrous glass reinforced polyester or epoxy resin with a minimum thickness equal to equivalent
size Schedule 40 steel pipe. Sleeves shall be constructed with integral collar or cold side shall be fitted
with a bonded slip-on flange or extended collar. In the case of masonry penetrations where sleeve is not cast-in,
voids shall be filled with latex mixed mortar cast to shape of sleeve and flange/external collar type sleeve
shall be assembled with butyl elastomer vapor barrier sealant through penetration to cold side surface vapor
barrier overlap and fastened to surface with masonry anchors. Integral cast-in collar type sleeve shall be flashed
[as indicated.] [with not less than 100 mm 4 inches of cold side vapor barrier overlap of sleeve surface.] Normally
noninsulated penetrating round surfaces shall be sealed to sleeve bore with mechanically expandable seals in
vapor tight manner and remaining warm and cold side sleeve depth shall be insulated with not less than [100]
[_____] mm [4] [_____] inches of foamed-in-place rigid polyurethane or foamed-in-place silicone elastomer. Vapor
barrier sealant shall be applied to finish warm side insulation surface. Warm side of penetrating surface shall
be insulated beyond vapor barrier sealed sleeve insulation for a distance which prevents condensation. Wires
in refrigerated space surface penetrating conduit shall be sealed with vapor barrier plugs or compound to prevent
moisture migration through conduit and condensation therein.
3.2.16.2 General Service Areas
Each sleeve shall extend through its respective wall, floor, or roof, and shall be cut flush with each surface.
Pipes passing through concrete or masonry wall or concrete floors or roofs shall be provided with pipe sleeves
fitted into place at the time of construction. Sleeves shall be of such size as to provide a minimum of 6 mm
1/4 inch all-around clearance between bare pipe and sleeves or between jacketed-insulation and sleeves. Except
in pipe chases or interior walls, the annular space between pipe and sleeve or between jacket over-insulation
and sleeve shall be sealed in accordance with Section 07 92 00 JOINT SEALANTS.
3.2.16.3 Waterproof Penetrations
Pipes passing through roof or floor waterproofing membrane shall be installed through a 5.17 kg/sq. m 17 ounce
copper sleeve, or a 0.81 mm 0.032 inch thick aluminum sleeve, each within an integral skirt or flange. Flashing
sleeve shall be suitably formed, and skirt or flange shall extend not less than 200 mm 8 inches from the pipe
and be set over the roof or floor membrane in a troweled coating of bituminous cement. The flashing sleeve shall
extend up the pipe a minimum of 50 mm 2 inches above the roof or floor penetration. The annular space between
the flashing sleeve and the bare pipe or between the flashing sleeve and the metal-jacket-covered insulation
shall be sealed as indicated. Penetrations shall be sealed by either one of the following methods.
a. Waterproofing Clamping Flange: Pipes up to and including 250 mm 10 inches in diameter passing through
roof or floor waterproofing membrane may be installed through a cast iron sleeve with caulking recess,
anchor lugs, flashing clamp device, and pressure ring with brass bolts. Waterproofing membrane shall
be clamped into place and sealant shall be placed in the caulking recess.
b. Modular Mechanical Type Sealing Assembly: In lieu of a waterproofing clamping flange and caulking
and sealing of annular space between pipe and sleeve or conduit and sleeve, a modular mechanical type
sealing assembly may be installed. Seals shall consist of interlocking synthetic rubber links shaped
to continuously fill the annular space between the pipe/conduit and sleeve with corrosion protected carbon
steel bolts, nuts, and pressure plates. Links shall be loosely assembled with bolts to form a continuous
rubber belt around the pipe with a pressure plate under each bolt head and each nut. After the seal
assembly is properly positioned in the sleeve, tightening of the bolt shall cause the rubber sealing
elements to expand and provide a watertight seal rubber sealing elements to expand and provide a watertight
seal between the pipe/conduit seal between the pipe/conduit and the sleeve. Each seal assembly shall
be sized as recommended by the manufacturer to fit the pipe/conduit and sleeve involved. The Contractor
electing to use the modular mechanical type seals shall provide sleeves of the proper diameters.
3.2.16.4 Fire-Rated Penetrations
Penetration of fire-rated walls, partitions, and floors shall be sealed as specified in Section 07 84 00 FIRESTOPPING.
3.2.16.5 Escutcheons
Finished surfaces where exposed piping, bare or insulated, pass through floors, walls, or ceilings, except in
boiler, utility, or equipment rooms, shall be provided with escutcheons. Where sleeves project slightly from
floors, special deep-type escutcheons shall be used. Escutcheon shall be secured to pipe or pipe covering.
3.2.17 Access Panels
Access panels shall be provided for all concealed valves, vents, controls, and items requiring inspection or
maintenance. Access panels shall be of sufficient size and located so that the concealed items may be serviced
and maintained or completely removed and replaced. Access panels shall be as specified in Section 05 50 13 MISCELLANEOUS
METAL FABRICATIONS.
3.2.18 Field Applied Insulation
Field installed insulation shall be as specified in Section 23 07 00 THERMAL INSULATION FOR MECHANICAL SYSTEMS,
except as defined differently herein.
3.2.19 Field Painting
Painting required for surfaces not otherwise specified, and finish painting of items only primed at the factory
are specified in Section 09 90 00 PAINTS AND COATINGS.
3.2.19.1 Color Coding
NOTE: Color coding for piping identification required by the using agency will
be developed and inserted in the "Color Code Schedule" in Section 09 90 00 PAINTS
AND COATINGS. For Air Force Installations, piping will be color-coded in accordance
with Attachment 4 of AFM 88-15.
Color coding for piping identification is specified in Section 09 90 00 PAINTS AND COATINGS.
3.2.19.2 Color Coding Scheme
NOTE: Color Coding Scheme may be deleted if not required in the project. Use
Sections with a 10 after the Section number and delete those with 20 for Army
projects, and vice versa.
A color coding scheme for locating hidden piping shall be in accordance with [Section 22 00 00 PLUMBING, GENERAL
PURPOSE][Section 22 00 70 PLUMBING, HEALTHCARE FACILITIES].
3.3 CLEANING AND ADJUSTING
Clean uncontaminated system(s) by evacuation and purging procedures currently recommended by refrigerant and
refrigerant equipment manufacturers, and as specified herein, to remove small amounts of air and moisture. Systems
containing moderate amounts of air, moisture, contaminated refrigerant, or any foreign matter shall be considered
contaminated systems. Restoring contaminated systems to clean condition including disassembly, component replacement,
evacuation, flushing, purging, and re-charging, shall be performed using currently approved refrigerant and refrigeration
manufacturer's procedures. Restoring contaminated systems shall be at no additional cost to the Government as
determined by the Contracting Officer. Water shall not be used in any procedure or test.
3.4 TRAINING COURSE
Conduct a training course for [_____] members of the operating staff as designated by the Contracting Officer.
The training period shall consist of a total [_____] hours of normal working time and start after the system
is functionally completed but prior to final acceptance tests. The field posted instructions shall cover all
of the items contained in the approved operation and maintenance manuals as well as demonstrations of routine
maintenance operations.
3.5 REFRIGERANT PIPING TESTS
NOTE: The following refrigerant system tests are for field fabricated refrigerant
piping systems. The tests do not apply to packaged, unitary equipment which
is charged at the factory.
Where applicable condensing temperature is over 54 degrees C (130 degrees F),
equipment and piping will be capable of withstanding leak pressure tests at
not less than the design pressure corresponding to the condensing pressure during
the higher ambient conditions (refer to ASHRAE 15 & 34).
After all components of the refrigerant system have been installed and connected, subject the entire refrigeration
system to pneumatic, evacuation, and startup tests as described herein. Conduct tests in the presence of the
Contracting Officer. Water and electricity required for the tests will be furnished by the Government. Provide
all material, equipment, instruments, and personnel required for the test. Provide the services of a qualified
technician, as required, to perform all tests and procedures indicated herein. Field tests shall be coordinated
with Section 23 05 93 TESTING, ADJUSTING, AND BALANCING OF HVAC SYSTEMS.
3.5.1 Preliminary Procedures
Prior to pneumatic testing, equipment which has been factory tested and refrigerant charged as well as equipment
which could be damaged or cause personnel injury by imposed test pressure, positive or negative, shall be isolated
from the test pressure or removed from the system. Safety relief valves and rupture discs, where not part of
factory sealed systems, shall be removed and openings capped or plugged.
3.5.2 Pneumatic Test
Pressure control and excess pressure protection shall be provided at the source of test pressure. Valves shall
be wide open, except those leading to the atmosphere. Test gas shall be dry nitrogen, with minus 55 degrees
C minus 70 degree F dewpoint and less than 5 ppm oil. Test pressure shall be applied in two stages before any
refrigerant pipe is insulated or covered. First stage test shall be at 69 kPa 10 psi with every joint being
tested with a thick soap or color indicating solution. Second stage tests shall raise the system to the minimum
refrigerant leakage test pressure specified in ASHRAE 15 & 34 with a maximum test pressure 25 percent greater.
Pressure above 690 KPa 100 psig shall be raised in 10 percent increments with a pressure acclimatizing period
between increments. The initial test pressure shall be recorded along with the ambient temperature to which
the system is exposed. Final test pressures of the second stage shall be maintained on the system for a minimum
of 24 hours. At the end of the 24 hour period, the system pressure will be recorded along with the ambient temperature
to which the system is exposed. A correction factor of 2 kPa 0.3 psi will be allowed for each degree C F change
between test space initial and final ambient temperature, plus for increase and minus for a decrease. If the
corrected system pressure is not exactly equal to the initial system test pressure, then the system shall be
investigated for leaking joints. To repair leaks, the joint shall be taken apart, thoroughly cleaned, and reconstructed
as a new joint. Joints repaired by caulking, remelting, or back-welding/brazing shall not be acceptable. Following
repair, the entire system shall be retested using the pneumatic tests described above. The entire system shall
be reassembled once the pneumatic tests are satisfactorily completed.
3.5.3 Evacuation Test
Following satisfactory completion of the pneumatic tests, the pressure shall be relieved and the entire system
shall be evacuated to an absolute pressure of 300 micrometers. During evacuation of the system, the ambient
temperature shall be higher than 2 degrees C 35 degrees F. No more than one system shall be evacuated at one
time by one vacuum pump. Once the desired vacuum has been reached, the vacuum line shall be closed and the system
shall stand for 1 hour. If the pressure rises over 500 micrometers after the 1 hour period, then the system
shall be evacuated again down to 300 micrometers and let set for another 1 hour period. The system shall not
be charged until a vacuum of at least 500 micrometers is maintained for a period of 1 hour without the assistance
of a vacuum line. If during the testing the pressure continues to rise, check the system for leaks, repair as
required, and repeat the evacuation procedure. During evacuation, pressures shall be recorded by a thermocouple-type,
electronic-type, or a calibrated-micrometer type gauge.
3.5.4 System Charging and Startup Test
Following satisfactory completion of the evacuation tests, the system shall be charged with the required amount
of refrigerant by raising pressure to normal operating pressure and in accordance with manufacturer's procedures.
Following charging, the system shall operate with high-side and low-side pressures and corresponding refrigerant
temperatures, at design or improved values. The entire system shall be tested for leaks. Fluorocarbon systems
shall be tested with halide torch or electronic leak detectors.
3.5.5 Refrigerant Leakage
If a refrigerant leak is discovered after the system has been charged, the leaking portion of the system shall
immediately be isolated from the remainder of the system and the refrigerant pumped into the system receiver
or other suitable container. Under no circumstances shall the refrigerant be discharged into the atmosphere.
3.5.6 Contractor's Responsibility
At all times during the installation and testing of the refrigeration system, take steps to prevent the release
of refrigerants into the atmosphere. The steps shall include, but not be limited to, procedures which will minimize
the release of refrigerants to the atmosphere and the use of refrigerant recovery devices to remove refrigerant
from the system and store the refrigerant for reuse or reclaim. At no time shall more than 85 g 3 ounces of
refrigerant be released to the atmosphere in any one occurrence. Any system leaks within the first year shall
be repaired in accordance with the requirements herein at no cost to the Government including material, labor,
and refrigerant if the leak is the result of defective equipment, material, or installation.