Specifications - City of Montpelier, Vermont

Title:Montpelier District HeatingCity of Montpelier, VT15990 – Testing, Adjusting, and BalancingIssue Date:September 28, 2012Page #:9 of 11F. Verify fan and motor operating characteristics and compare to manufacturer’s fancurve.G. Where air systems have a variable speed drive, set at 90% speed and adjustsheaves to deliver required air at this speed.H. Prepare schematic diagrams of system “asbuilt” ductwork to facilitate reporting.3.5 HYDRONIC SYSTEM BALANCING PROCEDUREA. Initiate balancing with discharge balance valve full open to allow full flow tosystem.B. Through a global control system command or other means, force all terminal andcoil control valves to full open position.C. Establish flow at all terminals and coils at design point. If system includes adiversity factor, proportionally balance all terminals and coils.D. Where hydronic systems do not have variable speed drives, adjust dischargebalance valve at pump as required to achieve design flows.E. Where hydronic systems have a variable speed drive, maintain discharge valves infull open position and allow VFD to maintain proper pump speed and flow.F. There are no balancing means installed in the hot water system in UnionElementary as the combination of a variable flow pumping system and three zonedifferential pressure measurements will provide adequate flow during operation.Instead of adjusting each terminal device, make measurements of flow atlocations coincident with the differential pressure transmitters to define eachtransmitter location’s required differential pressure.3.6 REVIEW SYSTEM CONSTRUCTION INTEGRITYA. General Ductwork Review: Review all ductwork for general conformance withDrawings. Identify fittings that do not comply with Drawings and Specificationsand may be causing excessive pressure drop or noise.B. Ductwork Sealing: Generally review and document the entire duct system toverify that system has been sealed to SMACNA seal class A standards (all seams,joints, and penetrations sealed).TESTING, ADJUSTING, AND BALANCING159909