2021-414-E-AMS-Riggs-Harrod Builders, Inc-SHSC Roof & HVAC Replacement

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Southern Human Services Center Smith Sinnett /2020072 HVAC and Roof Renovations Orange County,North Carolina Hydronic Piping 23 21 13 - 5 E.No system or part of the system shall be insulated until it has been successfully tested.If required for additional pressure load under test,provide temporary restraints at expansion joints or isolated them during test. F.All hydronic piping shall be hydrostatically tested to 150 psi for a period of four (4)hours minimum. 1.Use ambient temperature water as a testing medium unless there is a risk of damage due to freezing.Another liquid that is safe for workers and compatible with piping may be used if approved by the Engineer. 2.While filling system,use vents installed at high points of system to release air.Use drains installed at low points for complete draining of test liquid. 3.Subject piping system to hydrostatic test pressure.Verify that stress due to pressure at bottom of vertical runs does not exceed 90 percent of specified minimum yield strength or 1.7 times "SE"value in Appendix A in ASME B31.9,"Building Services Piping." 4.After hydrostatic test pressure has been applied for at least 10 minutes,examine piping, joints,and connections for leakage.Eliminate leaks by tightening,repairing,or replacing components,and repeat hydrostatic test until there are no leaks. 5.No pressure drop shall occur during test period. 6.Prepare written report of testing. G.Provide pumps,appropriately scaled gauges,calibrated instruments and test equipment, temporary piping,and personnel for tests.Remove all test equipment and drain pipes after completion of testing. H.If piping system is drained after testing and left empty or untreated for more than 3 days,add Nalco 2572 or equivalent at recommended dosages for dry system lay-up. 3.03 FLUSHING AND CLEANING OF PIPING SYSTEMS A.Notify Engineer and Owner/CxA at least four (4)days in advance.Do not flush any piping system or portion thereof without prior submission and approval of flushing and cleaning plan. B.General: 1.All hydronic piping systems shall be tested and flushed.All temporary equipment,utilities, and materials,including water,required to perform the tests and flushing shall be the responsibility of the contractor.Tests and flushes shall be witnessed by the Engineer or Owner's representative.The contractor shall perform pre-testing so that the Engineer may witness the final test and flush only.If more than one test and flush are required,contractor shall schedule these with the Engineer's site observation schedule.Submit contractor's testing and flushing plan,indicating how the system will be divided for flushing,chemical injection points,temporary bypass piping,temporary drains,etc. 2.Test fluid shall be clean water 3.Flush fluid shall be clean water with listed cleaning chemicals 4.Fill fluid shall be clean water C.Flushing and Fill: 1.Flush entire piping system until clean.Flush velocity shall be minimum of 5 fps through all sections of the system. 2.Contractor shall provide portable pumping apparatus.Provide temporary materials,valves, equipment,and infrastructure,required to create bypass(es)for a closed system to perform flush(es).Bypass permanent building pumps during flush.Remove any devices that could be clogged or damaged prior to flushing.Provide a grade 18-8 stainless steel screen with 3/16 inch diameter holes at 18 holes per square inch in system strainers.Install #100 mesh startup liner in system strainer with metal screen.Operate valves as necessary to ensure all sections of the system are flushed for the required time period. 3.Provide temporary piping to bypass coils,control valves,and other factory cleaned equipment,as wells as equipment subject to damage. 4.Dissolve the following chemicals in the system (listed in piunds per 1,000 gallons of system water): a.EDTA 40 lbs b.CITRIC ACID 35 LBS DocuSign Envelope ID: 94E7997D-4F29-42F6-A9B4-0A160438D2A6