Cleaver-Brooks CBH 40 - Page 14

Chapter 1-General Description and Principles of Operation
resetting to start the burner after a low water shut-
down.
(b) Starts and stops the feedwater pump (if used)
to maintain water at the proper operating level.
NOTE; Determine that control is plumb after
shipment and installation and throughout
operating life.
AUXILIARY LOW WATER CUTOFF
(Not shown) (Optional equipment)
This float-operated control breaks the circuit to
stop burner operation in the event boiler water
drops below the master low water cutoff point.
Manual reset type (optional equipment) requires
manual resetting in order to start the burner after
a low water condition.
LOW WATER CUT-OFF
(Hot Water Boiler) (Figure 1-3)
A
float operated control that breaks a circuit to
stop burner operation if water level in the boiler
drops below a safe operating point.
WATER COLUMN (Figure 1-2)
This assembly houses the low water cutoff and
pump control and includes the water gage glass,
gage glass shutoff cocks, and trycocks. The gage
glass provides a means for visually determining
water level.
WATER COLUMN DRAIN VALVE (Figure 1-2)
The water column drain valve is provided so that
the water column and its piping can be flushed
regularly to assist in maintaining cross-connecting
piping and float bowl clean and free of sediment. A
LOW GAS
PRESSURE SWITCH
GAS PILOT
PRESSURE REGULATOR
similar drain valve is furnished with auxiliary low
water cutoff (optional equipment) for same pur-
pose.
WATER GAGE GLASS DRAIN VALVE
(Figure 1-2)
This valve is provided to flush the gage glass.
TEST VALVE (Figure 1-2)
This valve allows the boiler to be vented during
filling, and facilitates routine boiler inspection.
PRESSURE GAUGE
(Stearn Boiler) (Figures 1-1 & 1-2)
Indicates boiler's internal pressure.
TEMPERATURE/PRESSURE GAUGE
(Hot Water Boiler) (Figure 1-3)
A
compound gauge that indicates boiler's internal
water temperature and water pressure.
STACK THERMOMETER (Figure 1-2)
Indicates temperature of vented flue gases. (Op-
tional)
SAFETY OR RELIEF VALVE (Figures 1-2 & 1-3)
A
safety valve(s) is used on a steam boiler to re-
lieve the boiler of pressures higher than the de-
signed pressure or the pressure designated by the
purchaser. A relief valve(s) is used on a hot water
boiler for the same purpose.
Safety and relief valves and their escape and drain
piping are to be installed to conform to the ASME
Code requirements. (Figure 1-7)
WARNING: Only the valve manufacturer or his
HIGH GAS
PRESSURE SWITCH
MAIN GAS VALVE
WITH INTEGRAL
PROOF OF CLOSURE
SWITCH
GAS PILOT
SOLENOID
VALVE
FIGURE 1-4. GAS TRAIN WITH TWO VALVES
1-6