SECTION 15581
HVAC HYDRONIC PIPING & SPECIALTIES
PART 1 - GENERAL
1.1 SUMMARY
A. This Section includes piping, special-duty valves, and hydronic specialties and buffer tank for Hydronic piping systems located inside the building; and condensate drain pip- ing.
1.2 DEFINITIONS
A. CPVC: Chlorinated polyvinyl chloride.
B. PVC: Polyvinyl chloride.
1.3 REFERENCES
A. Section 15000 – Plant Piping-General
B. Section 15008 – Detail Piping Specification – Mill Type Steel Pipe & Fittings
C. Section 15018 – Detail Piping Specification – Copper & Copper Alloy Pipe, Tubing and Fittings.
D. Section 15020 – Detail Piping Specification – Polyvinyl Chloride (PVC) Pipe & Fit- tings.
1.4 COORDINATION
A. Coordinate HVAC hydronic piping work with Process hydronic piping work.
B. Coordinate layout and installation of hydronic piping and suspension system compo- nents with other construction, including light fixtures, HVAC equipment, and partition assemblies.
C. Coordinate pipe sleeve installations for foundation wall penetrations.
D. Coordinate pipe fitting pressure classes with products specified in related Sections.
E. Coordinate size and location of concrete bases. Cast anchor-bolt inserts into base. Concrete, reinforcement, and formwork requirements are specified in Division 3 Sec- tions.
F. Coordinate installation of pipe sleeves for penetrations through exterior walls and floor assemblies.
PART 2 - PRODUCTS
2.1 MANUFACTURERS
A. Available Manufacturers: Subject to compliance with requirements, manufacturers of- fering products that may be incorporated into the Work include, but are not limited to, the following:
1. ITT Bell & Gossett
2.2 PIPING MATERIALS
A. General: Refer to Part 3 "Piping Applications" Article for applications of pipe and fit- ting materials.
2.3 STEEL PIPE & FITTINGS
A. See Specification Section 15008 – Detail Piping Specification – Mill Type Steel Pipe and Fittings.
2.4 COPPER TUBE AND FITTINGS
A. See Specification Section 15018 – Detail Piping Specification – Copper & Copper Al- loy Pipe, Tubing and Fittings.
B. Wrought-Copper Unions: ASME B16.22.
C. Solder Filler Metals: ASTM B 32, 95-5 tin antimony.
D. Brazing Filler Metals: AWS A5.8, Classification BAg-1 (silver).
2.5 PLASTIC PIPE AND FITTINGS – CONDENSATE DRAINS
A. See Specification Section 15020 – Detail Piping Specification – Polyvinyl Chloride (PVC) Pipe and Fittings.
B. PVC Plastic Pipe: ASTM D 1785, Schedules 40 and 80, plain ends.
C. PVC Plastic Pipe Fittings: Socket-type pipe fittings, ASTM D 2466 for Schedule 40 pipe; ASTM D 2467 for Schedule 80 pipe.
1. PVC Solvent Cement: ASTM D 2564.
2.6 VALVES – HYDRONIC SPECIALTY
A. Calibrated Balancing Valves (Circuit Setters), NPS 2 and Smaller: Bronze body, ball type, 125-psig working pressure, 250 deg F maximum operating temperature, and hav- ing threaded ends. Valves shall have calibrated orifice or venturi, connections for port- able differential pressure meter with integral seals, and be equipped with a memory stop to retain set position.
2.7 HYDRONIC SPECIALTIES
A. Manual Air Vent: Bronze body and nonferrous internal parts; 150-psig working pres- sure; 225 deg F operating temperature; manually operated with screwdriver or thumb- screw; with NPS 1/8 discharge connection and NPS 1/2 inlet connection.
B. Automatic Air Vent: Designed to vent automatically with float principle; bronze body and nonferrous internal parts; 150-psig working pressure; 240 deg F operating tempera- ture; with NPS 1/4 discharge connection and NPS 1/2 inlet connection.
PART 3 - EXECUTION
3.1 PIPING APPLICATIONS
A. Hydronic systems, NPS 2 and Smaller: Match existing piping. Options available in- clude the following: Aboveground, use Type L or K copper tubing with soldered joints or Schedule 40 steel pipe with threaded joints.
1. Utilize dielectric unions were copper piping is joined to steel piping.
B. Condensate Drain Lines: Schedule 40, PVC pipe with solvent-welded joints.
3.2 VALVE APPLICATIONS
A. General-Duty Valve Applications: Unless otherwise indicated, use the following valve types. Valves are specified in Section 15580 – HVAC Valves.
1. Shutoff Duty: ball valves & butterfly valves.
2. Throttling Duty: ball valves & butterfly valves.
B. Install shutoff duty valves at each branch connection to supply mains, at supply con- nection to each piece of equipment, unless only one piece of equipment is connected in the branch line. Install throttling duty valves at each branch connection to return mains, at return connections to each piece of equipment, and elsewhere as indicated.
3.3 PIPING INSTALLATIONS
A. Install groups of pipes parallel to each other, spaced to permit applying insulation and servicing of valves.
B. Install drains, consisting of a tee fitting, NPS 3/4 ball valve, and short NPS 3/4 threaded nipple with cap, at low points in piping system mains and elsewhere as required for system drainage.
1. Provide threaded hose connections on all drains with screw-on hose caps.
3.4 HANGERS AND SUPPORTS
A. Hanger, support, and anchor devices are specified in Division 15 "Supports, Anchors, Sleeves, and Sealing for HVAC Systems" Comply with requirements below for maxi- mum spacing of supports.
B. Install the following pipe attachments:
1. Adjustable steel clevis hangers for individual horizontal piping less than 20 feet long.
2. Adjustable roller hangers and spring hangers for individual horizontal piping 20 feet or longer.
3. Pipe Roller: MSS SP-58, Type 44 for multiple horizontal piping 20 feet or long- er, supported on a trapeze.
4. Spring hangers to support vertical runs.
5. On plastic pipe, install pads or cushions on bearing surfaces to prevent hanger from scratching pipe.
C. Install hangers for steel piping with the following maximum spacing and minimum rod sizes:
1. NPS 3/4: Maximum span, 7 feet; minimum rod size, 1/4 inch.
2. NPS 1: Maximum span, 7 feet; minimum rod size, 1/4 inch.
3. NPS 1-1/2: Maximum span, 9 feet; minimum rod size, 3/8 inch.
4. NPS 2: Maximum span, 10 feet; minimum rod size, 3/8 inch.
D. Install hangers for drawn-temper copper piping with the following maximum spacing and minimum rod sizes:
1. NPS 3/4: Maximum span, 5 feet; minimum rod size, 1/4 inch.
2. NPS 1: Maximum span, 6 feet; minimum rod size, 1/4 inch.
3. NPS 1-1/2: Maximum span, 8 feet; minimum rod size, 3/8 inch.
4. NPS 2: Maximum span, 8 feet; minimum rod size, 3/8 inch.
E. Plastic Piping Hanger Spacing: Space hangers according to pipe manufacturer's written instructions for service conditions. Avoid point loading. Space and install hangers with the fewest practical rigid anchor points.
F. Support vertical runs at roof, at each floor, and at 10-foot intervals between floors.
3.5 PIPE JOINT CONSTRUCTION
A. Refer to section "Basic HVAC Materials and Methods" for joint construction require- ments for soldered and brazed joints in copper tubing; threaded, welded, and flanged joints in steel piping; and solvent-welded joints for PVC and CPVC piping.
3.6 HYDRONIC SPECIALTIES INSTALLATION
A. Install manual air vents at high points in piping, at heat-transfer coils, and elsewhere as required for system air venting. Were access is limited, install tubing with remote mounted manual vent installed at end of tubing.
B. Install automatic air vents at high points of system piping in individual structures, at heat-transfer coils, and elsewhere as required for system air venting where manual vents cannot easily be accessed.
3.7 FIELD QUALITY CONTROL
A. Prepare hydronic piping according to ASME B31.9 and as follows:
1. Leave joints, including welds, uninsulated and exposed for examination during test.
2. Provide temporary restraints for expansion joints that cannot sustain reactions due to test pressure. If temporary restraints are impractical, isolate expansion joints from testing.
3. Flush system with clean water. Clean strainers.
4. Isolate equipment from piping. If a valve is used to isolate equipment, its closure shall be capable of sealing against test pressure without damage to valve. Install blinds in flanged joints to isolate equipment.
5. Install safety valve, set at a pressure no more than one-third higher than test pres- sure, to protect against damage by expanding liquid or other source of overpres- sure during test.
B. Perform the following tests on hydronic piping:
1. Use ambient temperature water as a testing medium unless there is risk of dam- age due to freezing. Another liquid that is safe for workers and compatible with piping may be used.
2. While filling system, use vents installed at high points of system to release trapped air. Use drains installed at low points for complete draining of liquid.
3. Check expansion tanks to determine that they are not air bound and that system is full of water.
4. Subject piping system to hydrostatic test pressure that is not less than 1.5 times the design pressure. Test pressure shall not exceed maximum pressure for any vessel, pump, valve, or other component in system under test. Verify that stress due to pressure at bottom of vertical runs does not exceed either 90 percent of specified minimum yield strength or 1.7 times "SE" value in Appendix A of ASME B31.9, "Building Services Piping."
5. After hydrostatic test pressure has been applied for at least 10 minutes, examine piping, joints, and connections for leakage. Eliminate leaks by tightening, repair- ing, or replacing components and repeat hydrostatic test until there are no leaks.
6. Prepare written report of testing.
3.8 ADJUSTING
A. Mark calibrated nameplates of pump discharge valves after hydronic system balancing has been completed, to permanently indicate final balanced position.
B. Perform these adjustments before operating the system:
1. Open valves to fully open position.
2. Check pump for proper direction of rotation.
3. Check air vents at high points of system and determine if all are installed and op- erating freely (automatic type), or bleed air completely (manual type).
END OF SECTION
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