CleaverBrooks 4WI, Operation, Service And Parts Manual

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Firetube Operation Basics
1-6 750-211 (revised 2009)
Promethean Boilers, Model 4WI Manual
2.
Water Gauge Glass Drain Valve : Provided to flush the gauge glass.
3.
Vent Valve : Allows the boiler to be vented during filling and facilitates routine boiler inspection as required by
ASME Code.
4.
Water Column Drain Valve : Provided so that the LWCO and its piping can be flushed regularly to assist in
maintaining cross-connecting piping and in keeping the float bowl clean and free of sediment. A similar drain
valve is furnished with auxiliary low water cutoff for the same purpose.
1.4.3 — Water Column
1.
Water Column Assembly : Houses the low water cutoff and pump control and
includes the water gauge glass and shutoff cocks.
FIGURE 1-7.
Water Column Assembly
1.4.4 — Steam Pressure Gauge and ALWCO
1.
Steam Pressure Gauge : Indicates boiler
internal pressure.
2.
Auxiliary Low Water Cutoff : Breaks the
circuit to stop burner operation in the event
boiler water drops below the master low
water cutoff point. Manual reset type
requires manual resetting in order to start
the burner after a low water condition.
FIGURE 1-8.
Steam Pressure Gauge and ALWCO (Hot Water)
1.4.5 — Safety Valve(s)
Safety Valves
: Prevent buildup over the design pressure of the pressure vessel. The size, rating, and number of
valves on a boiler is determined by the ASME Boiler Code. The safety valves and the discharge piping are to be
installed to conform to the ASME Code requirements. The installation of a valve is of primary importance to its
service life. A valve must be mounted in a vertical position so that discharge piping and code-required drains can be
properly piped to prevent buildup of back pressure and accumulation of foreign material around the valve seat area.
Apply only a moderate amount of pipe compound to male threads and avoid over-tightening, which can distort the
seats. Use only flat-jawed wrenches on the flats provided. When installing a flange connected valve, use a new gas-
ket and draw the mounting bolts down evenly. Do not install or remove side outlet valves by using a pipe or wrench
in the outlet.