Specifications - City of Montpelier, Vermont

Title:Montpelier District HeatingCity of Montpelier, VT15055– Basic Piping Materials and MethodsIssue Date:September 28, 2012Page #:8 of 102. Install dielectric waterway fittings to connect piping materials ofdissimilar metals in wet piping systems.3. Bronze bodied valves and devices installed in steel piping systems do notrequire dielectric fittings when both connections are made with steelpiping. Iron bodied valves and devices installed in copper systems requiredielectric fittings.D. Install horizontal strainers on steam systems with the wye oriented horizontally.Install horizontal strainers immediately preceding steam traps horizontally withwye oriented vertically down. Install horizontal strainers for water systems withwye oriented vertically down.E. Welded forged steel branch connections (“WeldOLets”, “ThreadOLets”, or“SockOLets”) may be used to create branch pipe taps in steel piping systemswhen the main to branch size ratio (main size divided by branch size) is not lessthan three to one, and the maximum branch pipe size is 2½" (See table below).Do not ‘fish mouth’ pipe to create branch piping runs.Main Size 2½” 3” 4” 5” 6” 8”Max Branch ¾” 1” 1¼” 1½” 2” 2½”F. Reductions in pipe size made with eccentric reducers shall have the tops level forwater piping and bottoms level for steam piping.G. Run all horizontal building drains at uniform pitch. Follow indicated linesgenerally, but make exact layout on the job to work actual fitting dimensions,align piping and avoid interferences. Unless otherwise specified or required bycode, provide proper support to maintain uniform fall of 1/4" per foot for lines 3inches and smaller and 1/8" per foot for lines larger than 3".H. Mechanical Sleeve Seals: Install per manufacturer’s recommended practices.Insure the structure penetration is properly sleeved, refer to Division 15, “BASICMECHANICAL MATERIALS AND METHODS”, and is properly sized. Thesleeve must be clean and dry prior to installation. Mechanical Sleeve Seals to beinstalled at all exterior wall penetrations, below grade.3.5 JOINTSA. Steel Pipe Joints:BASIC PIPING MATERIALS AND METHODS150558