Crown Boiler FSZ080, Руководство по установке

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15
VIII System Piping
WARNING
• Install boiler so that the electrical components are protected from water (dripping,
spraying, rain, etc.) During appliance operation and service (circulator replacement, etc.).
• Operation of this boiler in a system having significant amounts of dissolved oxygen can
cause severe heat exchanger corrosion damage.
• Do not use toxic additives, such as automotive antifreeze, in a hydronic system.
• Pipe safety valve discharge to a safe location. The safety valve may discharge steam or
scalding hot water.
• Do not install a valve in the safety valve discharge line.
• Do not move safety valve from factory location.
• Do not plug safety valve discharge. Blocking the safety valve may result in boiler
explosion.
Figure 8.1 shows recommended near boiler piping for most common types of gravity return steam systems. Additional
information on steam system design may be found in the
I=B=R
Guide RHH published by the Air-Conditioning, Heating and
Refrigeration Institute (AHRI).
One of the primary purposes of this near boiler piping is to separate tiny water droplets from the steam exiting the boiler
so that “dry” steam is sent to the system. If the near boiler piping is not correct, wet steam will enter the system and the
following problems may occur:
•
Short cycling on low water
•
Boiler or system Flooding
•
Hammering
•
Failure to heat one or more radiators
Avoid the common piping mistakes shown in Figure 8.2. This applies even if the existing boiler has one of the piping
mistakes shown in Figure 8.2 and appears to be working. If two or more steam mains must be connected to the boiler, connect
a separate take-off for each main into the header between the riser(s) and equalizer. Also note the following points:
1) A size reduction must be made to connect the header to the equalizer. This reduction must be made in the vertical
equalizer line. Do not make this size reduction in the horizontal header .
2) One-pipe steam systems require air vents on each radiator, as well as at the end of each main. For the system to work
properly, these vents must be properly installed, sized, and be in good condition. Inspect and replace any defective vents.
If there are no vents at the ends of the mains, install them.
3) Do not attempt to manifold multiple FSZ boilers with gravity returns.
4) For installations with condensate or boiler feed pumps, follow the pump manufacturer’s piping instructions. Such
systems generally do not require Hartford loops.
5) Do not use a check valve in place of, or in addition to, a Hartford loop on a gravity return system.
6) Pipe the fill connection from a clean source of cold water. When the water supply is from a well, make sure that a strainer
is installed in the well system.
7) The “drop header” arrangement shown as “Alternate Piping Method” in Fig 8.1 is useful when there is limited vertical
clearance above the boiler.