VA 22 35 00-2010 DOMESTIC WATER HEAT EXCHANGERS.pdf

1、02-10 22 35 00 - 1 SECTION 22 35 00 DOMESTIC WATER HEAT EXCHANGERS SPEC WRITER NOTE: Delete between /-/ if not applicable to project. Also delete any other item or paragraph not applicable in the section and renumber the paragraphs. PART 1 - GENERAL 1.1 DESCRIPTION: This section describes the requir

2、ements for domestic hot water heat exchangers including thermometers and all necessary accessories, connections and equipment. 1.2 RELATED WORK: A. Section 09 91 00, PAINTING: Preparation and finish painting. B. Section 22 05 11, COMMON WORK RESULTS FOR PLUMBING. C. Section 22 11 23, DOMESTIC WATER

3、PUMPS: Circulating Pump. D. Section 23 07 11, HVAC, PLUMBING, AND BOILER PLANT INSULATION: Heater Insulation. E. Section 22 05 19, METERS AND GAGES FOR PLUMBING PIPING, 22 05 23, GENERAL-DUTY VALVES FOR PLUMBING PIPING, and 22 11 00, FACILITY WATER DISTRIBUTION: Piping, Fittings, Valves and Gages. 1

4、.3 SUBMITTALS: A. Submit manufacturers literature and data pertaining to the water heater in properly bound package, in accordance with Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, AND SAMPLES. Include the following as a minimum: 1. Heat Exchangers. 2. Pressure and Temperature Relief Valves. 3. St

5、eam Control Valves. 4. Thermometers. 5. Pressure Gages. 6. Vacuum Breakers. B. Equipment components in contact with potable water shall meet NSF compliance requirements in document NSF 61, “Drinking Water System Components Health Effects. C. A form U-1 or other documentation stating compliance with

6、the ASME Boiler and Pressure Vessel code. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 22 35 00 - 2 1.4.APPLICABLE PUBLICATIONS: A. The publications listed below form a part of this specification to the extent referenced. The publications ar

7、e referenced in the text by the basic designation only. B. American National Standard Institute (ANSI): Z21.22-00/4.4A-00 Relief Valves for Hot Water Supply systems C. American Society of Mechanical Engineers (ASME): B1.20.1-01 . Pipe Threads, General Purpose B16.5-03 . Pipe Flanges and Flanged Fitt

8、ings, NPS through NPS 24 B16.24-06 Cast Copper Alloy Pipe Flanges, Class 150, 300,600, 900, 1500, 2500 PTC 25.3-02 Pressure Relief Devices Section IV-07 Heating Boilers Section VIII-07 Pressure Vessels Division 1 SPEC WRITER NOTE: Delete between /_/ if not applicable to project. Also delete any othe

9、r item or paragraph not applicable in the section and renumber the paragraphs. 1.5 AS-BUILT DOCUMENTATION A. The electronic documentation and copies of the Operations and Maintenance Manual, approved submittals, shop drawings, and other closeout documentation shall be prepared by a computer software

10、 program complying with Section 508 of the Rehabilitation Act of 1973, as amended (29 U.S.C 794d). The manufacturer or vendor of the software used to prepare the electronic documentation shall have a Voluntary Product Accessibility Template made available for review and included as part of the Opera

11、tions and Maintenance Manual or closeout documentation. All available accessibility functions listed in the Voluntary Accessibility Template shall be enabled in the prepared electronic files. As Adobe Acrobat is a common industry format for such documentation, following the document, “Creating Acces

12、sible Adobe PDF files, A Guide for Document Authors“ that is maintained and made available by Adobe free of charge is recommended.” B. Four sets of manufacturers literature and data updated to include submittal review comments and any equipment substitutions. C. Four sets of operation and maintenanc

13、e data updated to include submittal review comments shall be inserted into a three ring binder. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 22 35 00 - 3 All aspects of system operation and maintenance procedures, including piping isometrics

14、, wiring diagrams of all circuits, a written description of system design, control logic, and sequence of operation shall be included in the operation and maintenance manual. The operations and maintenance manual shall include troubleshooting techniques and procedures for emergency situations. Notes

15、 on all special systems or devices such as damper and door closure interlocks shall be included. A List of recommended spare parts (manufacturer, model number, and quantity) shall be furnished. Information explaining any special knowledge or tools the owner will be required to employ shall be insert

16、ed into the As-Built documentation. PART 2 - PRODUCTS 2.1 SHELL AND TUBE, DOMESTIC WATER HEAT EXCHANGERS: A. The shell and tube heat exchangers shall be semi-instantaneous type, /vertical/ /horizontal/ with water in the shell and steam in the tubes. The shell and tube heat exchanger shall be a packa

17、ged assembly of tank, heat exchanger coils, controls, and specialties constructed of ASME code copper lined, carbon steel shell with 1035 kPa (150 psig) minimum working pressure. B. The stand shall be factory fabricated for floor mounting. C. The tappings shall be factory fabricated of materials com

18、patible with heat exchanger shell. For sizes 50 millimeter or DN50 (NPS 2) and smaller, the tappings shall be threaded ends fabricated in accordance to ASME B1.20.1. For sizes 65 millimeters or DN65 (NPS 2-1/2) and larger, the tappings shall be flanged according to ASME B16.5 for steel and stainless

19、 steel flanges and ASME 16.24 for copper and copper alloy flanges. D. Shell insulation shall comply with ASHRAE 890.1 and suitable for operating temperature. The entire shell and nozzles shall be completely surrounded except connections and controls. E. The heat exchanger coils shall be constructed

20、from copper and fabricated in a helix wound for steam heating medium. The pressure rating shall be equal to or greater than the steam supply pressure plus 50%. F. The temperature controls shall be based upon an adjustable temperature transmitter that operates a control valve and is capable of mainta

21、ining outlet water temperature within 2 degrees C (4 degrees F) of setting. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 22 35 00 - 4 G. Safety control shall be automatic, high temperature limit shutoff device. H. The relief valves shall be

22、ASME rated and stamped for combination temperature and pressure relief valves. One or more relief valves with total relieving capacity at least as great as heat input shall be included. The pressure setting shall be less than the working pressure rating of the heat exchanger minus 10 percent. /I. Th

23、e Pressure storage vessel shall be all welded construction and ASME Code Section VIII stamped for a working pressure of 1035 kPa (150 psig) . The storage tank shall be / carbon steel with a minimum of 16 mm (5/8 inch) thick cement lining / carbon steel with 4.9 kg/sq. meter (3 lb./sq. ft) copper lin

24、ing / solid copper-silicon, grade SB-96 / solid stainless steel type / 304 / 316L /epoxy lined/. The storage vessel shall be provided with a fiberglass insulation system in compliance with ASHRAE 90.1./ J. Controls: 1. Steam control valve shall regulate the control of steam flow to the heating coil

25、to control water temperature and shall be electronic operated. The outlet water temperature shall not vary more than 1 degrees C ( 2.5 degrees F). 2. A drip trap, steam condensate trap (if required), Y strainer, vacuum breaker, and pressure gage shall be factory sized and piped with steam control va

26、lve. 3. A normally closed solenoid Valve shall be rated at 5 amps, 120-volt solenoid valve shall close the steam supply to the heating coil, should the water temperature in the tank reach the high set point. 2.2 CIRCULATING DOMESTIC WATER HEAT EXCHANGERS A. A packaged /small capacity/ /large capacit

27、y/ with hot water storage tank shall be provided with circulator, heat exchanger coil, controls, and specialties. The domestic water heat exchanger with circulator shall be based upon a standard flow arrangement with water from bottom of storage tank circulated across the heat exchanger coil and ret

28、urned to tank. B. A hot water outlet shall be included at the top of the tank. C. A temperature sensor shall be located inside the storage tank. D. A circulating pump complying with UL 778, all bronze construction, overhung impeller, and separately coupled inline pump shall be Provided by IHSNot for

29、 ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 22 35 00 - 5 included. The pump shall have mechanical seals. The working pressure shall be rated at 860 kPa (125 psig). E. The stand shall be factory fabricated for floor mounting. F. The tappings shall be factory fabr

30、icated of materials compatible with heat exchanger shell. For sizes 50 millimeters or DN50 (NPS 2) and smaller, the tappings shall be threaded ends fabricated in accordance to ASME B1.20.1. For sizes 65 millimeters or DN65 (NPS 2-1/2) and larger, the tappings shall be flanged according to ASME B16.5

31、 for steel and stainless steel flanges and ASME 16.24 for copper and copper alloy flanges. G. Shell insulation shall comply with ASHRAE 890.1 and suitable for operating temperature. The entire shell and nozzles shall be completely surrounded except connections and controls. H. The heat exchanger coi

32、ls shall be constructed from copper and fabricated in a helix wound for steam heating medium. The pressure rating shall be equal to or greater than the steam supply pressure plus 50%. I. The temperature controls shall be based upon an adjustable temperature transmitter that operates a control valve

33、and is capable of maintaining outlet water temperature within 2C (4F) of setting. J. Safety control shall be automatic, high temperature limit shutoff device. K. The relief valves shall be ASME rated and stamped for combination temperature and pressure relief valves. One or more relief valves with t

34、otal relieving capacity at least as great as heat input shall be included. The pressure setting shall be less than the working pressure rating of the heat exchanger minus 10 percent. 2.3 THERMOMETERS: A. Thermometers shall be rigid stem or remote sensing, dial type with an aluminum, black metal, sta

35、inless steel, or chromium plated brass case. The thermometer shall be back connected, mercury, vapor, BI-metal or gas actuated, with circular dial 90 mm (3 1/2 inches) in diameter graduated from 4 to 100C (40 to 210F), with two-degree graduations guaranteed accurate within one scale division. The so

36、cket shall be separable, double-seat, micrometer-fittings, with extension neck not less than 65 mm (2 1/2 inches) to clear tank or pipe covering. The thermometer shall be suitable for 20 mm (3/4 inch) pipe threads. Provided by IHSNot for ResaleNo reproduction or networking permitted without license

37、from IHS-,-,-02-10 22 35 00 - 6 Thermometers may be consoles mounted with sensor installed in separate thermometer well. 2.4 SAFETY VALVES FOR SHELL AND STEAM HEATERS: A. Separate temperature relief valve and pressure relief valve or combination pressure/temperature relief valves shall be provided o

38、n each water heater. The safety valve discharge shall be routed to nearest floor drain. B. Temperature Relief Valves shall be constructed from all brass or bronze material. The temperature relief valves shall be automatic, self-closing reseating type valve, equipped with a noncorrosive metal thermos

39、tat with bulb extending into tank that can be manually displaced from its seat for test purposes. The temperature relief valve shall be tested and approved as to its BTU capacity by ASME or an independent laboratory satisfactory to the Contracting Officer. In no case shall total rated BTU relieving

40、capacity of temperature relief valve, or valves, be less than BTU input into water heater. Temperature relief valve shall be completely open before temperature reaches 98C (210F) and shall close when temperature goes below 93C (200F). C. Pressure relief valves shall conform to requirements of ASME,

41、Section IV. BTU relieving capacity of pressure relief valve, or valves, shall be not less than BTU input of the water heater. The pressure relief shall be set at 690 kPa (100 psig) pressure. D. A double solenoid safety system shall be provided for each shell and steam coil heater to function as a sa

42、fety over temperature prevention system. System shall consist of aquastat, pilot light, solenoid steam safety valve and solenoid water safety valve located in the control circuit. The aquastat shall be set at 60C (140F). 2.5 DOMESTIC HOT WATER COMPRESSION TANKS A. A steel pressure rated tank constru

43、cted with welded joints and factory installed butyl rubber diaphragm shall be installed as scheduled. The air pre-charge shall be set to minimum system operating pressure at tank. B. The tappings shall be factory fabricated steel, welded to the tank and include ASME B1.20.1 pipe thread. C. The inter

44、ior finish shall comply with NSF 61 barrier materials for potable water tank linings and the liner shall extend into and through the tank fittings and outlets. D. The air charging valve shall be factory installed. Provided by IHSNot for ResaleNo reproduction or networking permitted without license f

45、rom IHS-,-,-02-10 22 35 00 - 7 2.6 HEAT TRAPS A. Heat traps shall be installed in accordance with ASHRAE 90.1, latest edition. 2.7 COMBINATION TEMPERATURE AND PRESSURE RELIEF VALVES A. The combination temperature and pressure relief valves shall be ASME rated and stamped and include a relieving capa

46、city at least as great as the heat input and include a pressure setting less than the water heaters working pressure rating. PART 3 - EXECUTION 3.1 INSTALLATION: A. The water heaters shall be installed on concrete bases. Refer to Specification Section 03 30 00, CAST-IN-PLACE CONCRETE and Section 22

47、05 11, COMMON WORK RESULTS FOR PLUMBING B. The water heaters shall be installed level and plumb. C. Water heaters shall be installed and connected in accordance with manufacturers written instructions. D. All pressure and temperature relief valves discharge shall be pipe to nearby floor drains. E. T

48、hermometers shall be installed on water heater inlet and outlet piping. F. The control thermostats shall be set for a maximum setting of 54C (130F). 3.2 LEAKAGE TEST: A. Before piping connections are made, the water heaters shall be tested at a hydrostatic pressure of 1375 kPa (200 psi) for water he

49、aters rated at less than 1103 kPa (160 psig) and 1654 kPa (240 psig) for units with an maximum working pressure of 1103 kPa (160 psig) or over. Any failed test shall be corrected and the water heater shall be retested at no additional cost to the VA. 3.3 PERFORMANCE TEST: A. Ensure that all of the remote water outlets will have a minimum of 49C (120F) and a maximum