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MAIN AIR VENT: for down flow systems or diaphragm type expansion tanks (not provided)
Before a system is filled with water, there is air in the pipes and radiation units• Some of the air will be
trapped as the system is filled. It is possible to eliminate most of this air through the air vents on the
radiation units• A main air vent will speed and simplify this process. The main air vent should be installed on the highest point in the supply main when all radiation is below the top of the boiler.
AUTOMATIC FILL VALVE (not provided)
For safe, efficient operation, a hot water system must be filled with water. Adding new water, when needed can be done manually (by use of a hand valve in the water supply line). This requires regular attention to the system's needs. An automatic fill valve or pressure reducing valve accomplishes this without attention. It is
installed in the supply line on hot water boilers only. The valve operates through water pressure
differentials. It does not require an electrical connection.
BURNER SOLENOID VALVE (provided)
The Beckett and Carlin oil burner's use a standard solenoid valve. Upon burner shut down, a standard solenoid valve stops the flow of oil to the nozzle. Without the solenoid valve, the oil pump continues to
pump oil to the burner nozzle until the burner motor winds down below the pumps
seconds. This allows the burner fan motor to
AQUASTAT RELAY CONTROL (provided)
The water temperature limit control in the aquastat relay is adjustable and may be set: as low as 140°F so long as return water temperatures to the boiler are no less than 120°F, or as high as 240°F so long as the
boiler and heating system have adequate circulation to remove the heat from the boiler otherwise steam may be created in the boiler. Refer back to SYSTEM PIPING section for more information.
DRAIN VALVE (provided)
The drain valve is a manually operated valve that provides a means of draining all the water from the boiler and heating system. It should be installed in the reducing tee where the return line enters the boiler.
CIRCULATOR (provided)
Every forced hot water system requires a circulator. A separate circulator or zone valve is required for each zone, if there are two or more zones. The circulator must have the capacity to provide the circulation required by the heating system. The circulator should be connected to the supply main and must be wired into the boiler's electrical system. See the SYSTEM PIPING section for piping configurations with the circulator located on the supply main piping using zone circulators or zone valves. When the piping is arranged with zone circulators and no bypass piping, the circulator provided with the boiler may be used as a zone circulator. Both piping arrangements allow the circulator to pump away from the expansion tank and show how the piping should be arranged to allow the heating system to be easily purged of air.
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