Systems with multiple zones may require an additional circulator. Consult manufacturer's data for valve pressure drops. When an indirect water heating system is used, it is recommended that a separate circulator be installed to meet the required flow and pressure drop conditions of the indirect water heater.
We recommend that the
The pressure relief valve is mounted on the boiler and must be piped to a drain. We recommend that all high points be vented and that purge valves be installed. A boiler installed above radiation level must be provided with a low water
The boiler piping system of a hot water heating boiler, that is connected to heating coils located in air handling units where they may be exposed to refrigerated air circulation, must be equipped with flow control valves or other automatic means to prevent gravity circulation of the boiler water during the cooling cycle.
A diaphragm expansion tank should be installed in the return line. A typical
PIPING DIAGRAMS
AIR
VENT
AIR
SCOOP
DIAPHRAGM
EXPANSION TANK
FEED
VALVE
PIPE PRESSURE
RELIEF VALVE
TO DRAIN
COLD
WATER
INLET
HEATING UNITS
SINGLE-ZONEPIPING
Fig.# 8997.1
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