Specifications - City of Montpelier, Vermont

Title:Montpelier District HeatingCity of Montpelier, VT15910 – Sequences of OperationsIssue Date:September 28, 2012Page #:2 of 111. The existing control system will expand and operate the new heatingequipment. The controls will have no connection to the Main Plantsystem.C. Union Elementary1. The existing control system will expand and operate the new heatingequipment. The controls will have no connection to the Main Plantsystem.D. Main Plant (State Steam Plant)1. The Main Plant’s controls will be an industrial Programmable LogicController.2. This controller will operate all the equipment in the main steam plant.3. This controller will monitor telemetry through the fiber optic network thisproject will construct; the network is primarily for the metering system butwill also allow the Main Plant to communicate to distributed controllersthat monitor temperature and differential pressure points. The Main Plantcontrols will operate the equipment in the plant via these points.PART 2– PRODUCTSNot UsedPART 3– EXECUTION3.1 CITY HALLA. Winter Operation, Using District Heat1. Lead/Lag Selection and Manual Valve Lineupa. The human operator shall manually command the lead item via thehuman machine interface (HMI) of this equipment:1.) P1 or P2 (building heating pumps)2.) P2.1 or P2.2 (heat exchanger pumps)3.) B1 or B2 (hot water boilers)b. The human operator shall line up the manual valves around theCity Hall load and at the connection to the heat exchanger forwinter operation and position winter/nonwinter valves asdescribed on the project drawings.2. Building Heat Enable/Disablea. When the outdoor air temperature is below 55 degrees F(adjustable) the controls shall command the system on for spaceheating.b. When the controls command space heating off, both pumps P1and P2 shall be off. Both boilers and their associated pumps shallbe off. P2.1 and P2.2 shall be off.SEQUENCE OF OPERATION159102