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HomeMy WebLinkAboutB17-0104_M1.0_1493223540.pdfMARK DESCRIPTION EFFECTIVE BTU/H BTU/H GPM TUBE TOTAL # OF LOOP GPM/LOOP P.D. MANIFOLD TUBING AREA (SF) PER SF CENTERS LENGTH LOOPS LENGTHS (FT) SIZE SIZE SZ-1 PATIO & STAIRS 330 150 49500 3.8 9 440 4 120 0.9 4.1 1" 1/2" TOTALS 330 49500 3.8 440 SNOWMELT ZONE SCHEDULE 1. HX-1 Heat Exchanger (Snowmelting) a. Provide (1) Tekmar 091/094 snow/ice sensor and socket. b. Provide (1) Tekmar 667 snowmelt control. c. Upon a call for snowmelting from snow/ice sensor, P-2 snowmelt pump shall start, P-1 heat exchanger pump shall be enabled, and boilers shall be enabled. P-1 heat exchanger pump shall be modulated by Tekmar control to maintain 120°F (adj) snowmelt supply temperature setpoint at TS-1 temperature sensor. d. Provide a 12-hour timer switch for manual override operation. e. Tekmar system shall be setup for WWSD (warm weather shut down) at approximately 45°F (adj). System shall not operate if outdoor temperature is above this setting. f. Tekmar control shall be setup for CWCO (cold weather cut off) at approximately 10°F (adj). System shall not operate if outdoor temperature is below this setting. 2. Pumps a. P-1 HX-1 heat exchanger pump: on whenever there is a call for snowmelting. Tekmar control shall modulate P-1 to maintain SMS temperature setpoint at TS-1 temperature sensor, 120°F (adj). b. P-2 snowmelt pump: on whenever there is a call for snowmelting. Sequence of Operation Mechanical Specifications Insulation 1. Piping Insulation Schedule: Service Thickness (in.) Type HWS/R (less than 1.5” pipe) 1.0 Fiberglass SMS/R (inside mechanical room) 1.0 Fiberglass SMS/R (buried) 1.0 Closed cell elastomeric Heating water piping and snowmelt piping (inside mechanical room) insulation shall be U.L. approved, white, all service, glass fiber, snap-on, pipe insulation. Insulate fittings with glass fiber blanket insulation and premolded PVC covers. Provide submittal. Snowmelt distribution piping buried outside shall be insulated with 1" flexible, closed-cell elastomeric insulation, AP Armaflex or equal. Product must meet requirements of ASTM C 534. Insulation shall have a maximum thermal conductivity of 0.27 Btu-in/h-ft2F at 75 F mean temperature. Buried insulation shall be wrapped in a waterproof tape, e.g. Densotape or approved equal. 2. Insulation shall be installed under all exterior snowmelt areas. Insulation shall be Dow Styrofoam Highload extruded polystyrene foam board insulation that has an R-5 per inch insulation value, and 2" thick. Insulation installed under traffic areas must be traffic rated. Piping 3. Heating water piping and snowmelt piping (inside mechanical room) shall be type 'L' copper, wrought copper fittings, and no lead solder. 4. PEX piping shall be supported by continuous cradles supplied by the manufacturer. 5. Snowmelt distribution piping buried underground outdoors shall be sized per plans and shall be PEX-a crosslinked polyethylene with an oxygen diffusion barrier, manufactured by the Engle method. 6. Copper pipe Valves and Specialties: Gate Valves: Bronze, Class 125, 200 lb. W.O.G. Ball Valves: Bronze, Class 125, 200 lb. W.O.G. Check Valves: Bronze, Class 125, 200 lb. W.O.G. Balancing Valves: 125 psig w.p. for 250F service tight shut-off, Illinois dual-purpose, balancing/shut-off valve, Hoffman, Sarco, or equivalent. 7. Support pipe with rod and clevis or clamps. No pipe tape allowed. 8. Provide expansion joints or loops on all heating water piping runs in excess of 50'. 9. Dielectric Unions - Furnish and install a dielectric union at all connections where non-ferrous material is in contact with ferrous material and fluid is not protected with corrosion inhibitors. 10. Grade and valve all heating water piping with ¾” hose end valves to permit drainage of the system. Vent all high points in equipment rooms as necessary with automatic air vents piped to convenient drain. All high points in system outside of equipment rooms with manual air vents as required to relieve air in the system. Antifreeze Solutions 11. Fill snowmelt system with 50% propylene glycol / 50% water solution, by volume, for freeze protection to -28°F and burst protection to -60°F. Include corrosion inhibitors. Snowmelt 12. Snowmelt tubing shall be 1/2" nominal diameter. Tubing shall be PEX-a crosslinked polyethylene with an oxygen diffusion barrier, manufactured by the Engle method in accordance with ASTM F 876. 13. Piping shall be installed in continuous loops, no splices allowed. Tube centers and the maximum loop lengths are specified in the Snowmelt Zone Schedule on the plans. For stairs, use 6" centers. 14. Tubing loops off each manifold shall be installed in equivalent lengths (+/- 5%). 15. The Contractor shall install manifolds as provided by the tubing manufacturer. The manifolds shall consist of a return header (including: balancing valve for each loop, compression fitting to receive tubes and air vent) and supply header (including: manual shut-off valve for each loop and compression fitting to receive tubes). 16. Snowmelt distribution piping shall be sized per plans. Piping shall be PEX-a crosslinked polyethylene with an oxygen diffusion barrier, manufactured by the Engle method. 17. Secure piping in snowmelt areas by attaching tubing to wire mesh using plastic tie straps, every 3' on straight runs and at apex of turn for any change of direction. No metal wiring shall be used. 18. Snowmelt system shall be pressure tested in accordance with tubing manufacturer's instructions as required for warranty protection. In the absence of manufacturer's instruction, pressurize the entire snowmelt system with compressed air. Charge system to a pressure of not less than 80 psig or more than 100 psig. Pressure test shall last for 24 hours with not less than a 2 psig drop. With system air charged, soap test all joint on and within the manifolds. After hydrostatic test pressure has been applied, examine piping, joints and connections for leakage. Eliminate any leaks as necessary & re-test. Any portion of tubing layout that rises as a result of being pressurized shall be re-secured to be at the proper level within the slab structure when poured. 19. Entire snowmelt system shall be left pressurized with monitoring pressure gauge throughout installation of concrete or sand/pavers. Continually monitor pressure on system to make certain tubing system remains intact with no leaks or punctures. 20. Manifolds shall be tagged to identify area served. Each connection on supply & return manifolds shall be permanently labeled with loop number. 21. Prior to final system fill and commissioning, the PEX tubing system and manifolds shall be chemically cleaned as prescribed by the tubing manufacturer. Supply all tools, connections, labor, and accessories necessary to properly remove all foreign material, chemical, and residue within the tubing system before permanently charging system and placing into operation. 22. After entire system has been properly cleaned and flushed, fill system with clean water to proper cold fill pressure. Add propylene glycol to the snowmelt system to the concentration specified using a positive displacement pump. Antifreeze fluid shall include corrosion inhibitors. Purge each individual loop to eliminate air pockets in the system. After purging remove fill connection to any potable water lines to prevent any possibility of contamination. 4/11/17 Snowmelt within Town of Vail Right of Way Must be on a seperate zone marked at the control box, TOV or ROW. Inspection required. 04/26/17