V. Piping and Trim
WARNING
Failure to properly pipe boiler may result in improper operation and damage to boiler or structure.
A.Design and install boiler and system piping to prevent oxygen contamination of boiler water. Sources of oxygen contamination are system leaks requiring addition of makeup water, fittings, and oxygen permeable materials in distribution system. Eliminate oxygen contamination by repairing system leaks, repairing fittings, using nonpermeable materials in distribution system, and eliminating open tanks in system, or isolating boiler from system with heat exchanger.
B.Install Safety (Relief) Valve in Tapping "E" (¾ NPT). See Figure 23. Use ¾ NPT x 3" nipple and ¾ NPT elbow provided. Safety (Relief) Valve must be installed with spindle in vertical position.
Figure 23: Trim Installation
WARNING
Safety (relief) valve discharge piping must be piped such that the potential of severe burns is eliminated. DO NOT pipe in any area where freezing could occur. DO NOT install any shut-off valves, plugs or caps. Consult Local Codes for proper discharge piping arrangement.
C.Install Drain Valve in Tapping "F" (2 NPT bushed to ¾ NPT). See Figure 23.
D.Connect supply and return piping to heating system. Maintain minimum ½ inch clearance from combustible materials.
1. For STEAM heating see Figure 24. Consult I=B=R Installation and Piping Guides.
2. For HOT WATER heating with Circulator (forced) see Figure 25 and 25A. Consult I=B=R Installation and Piping Guides.
3. If boiler is used in connection with refrigeration systems, boiler must be installed with chilled medium piped in parallel with heating boiler using appropriate valves to prevent the chilled medium from entering the boiler. See Figure 26. Also consult I=B=R Installation and Piping Guides.
4. If boiler is connected to heating coils located in air handling units where they may be exposed to refrigerated air, boiler piping must be equipped with flow control valves to prevent gravity circulation of boiler water during cooling system operation.
NOTICE
Do not use softened water in steam boilers. Accelerated boiler corrosion will result. Tie in fresh water supply to the boiler upstream of a water softener.
Oxygen contamination of boiler water will cause corrosion of iron and steel boiler components, and can lead to boiler failure. Burnham's Standard Warranty does not cover problems caused by oxygen contamination of boiler water or scale (lime)
Before using copper for steam piping, consider the following characteristics of copper piping:
1)high coefficient of thermal expansion can induce mechanical stresses and cause expansion/ contraction noises if not accounted for in the piping system design and installation,
2)high heat transfer rate (heat loss) of uninsulated copper piping must be included in the normal piping and pickup factors used to size the boiler,
3)soldering or brazing pastes and fluxes that end up in the system can cause poor heat transfer, surging, an unsteady water line and wet steam if not thoroughly removed during the boil out procedure and,
4)galvanic corrosion of the adjoining metal may occur due to dissimilar metals in certain water chemistries if dielectric unions are not used.
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