Form 2055
7
Revision Date 5/1/2015
2 . 1 . 2 S T E A M P R E S S U R E O P E R A T I N G C O N T R O L
The steam pressure in the boiler is regulated by the Boiler Operator. This is a pressure control
which senses the steam pressure and turns the boiler on and off accordingly. This control must be
operationally tested. Adjust the pressure setting on the control to a pressure less than the boiler
pressure (as shown on the boiler pressure gauge). The control should turn the boiler off. Restore
the control setting to normal. The boiler should cycle on.
2 . 1 . 3 H I G H L I M I T C O N T R O L
At least two additional pressure controllers are provided as high limit controls. They are set at a
pressure above the operator to act as a back-up should the operator fail. The high limit control
must be operationally tested. With the boiler operating, decrease the pressure setting of the limit
control below the current pressure of the boiler. The boiler should cycle off. Restore the high limit
control setting to normal (pushing the reset button if it is a manual reset type). The boiler should
now cycle on.
2 . 1 . 4 L O W W A T E R C U T - O F F ( S )
Most boilers are supplied with at least one float or electric probe type control, designed to sense
the level of the water in the boiler. It operates to shut off the boiler if the water level drops below its
sensing level. The low water cut-off controls must be operationally tested by manually lowering
the boiler water level (by opening the drain valve). The boiler should cycle off when the water level
drops below the control point of the low water cut-off. When the water level is restored, the boiler
should cycle back on. Depress the manual reset button of devices which require manual reset in
order to restore the boiler to operation. Carefully read the enclosed literature on the low water cut-
off controls, particularly installing, operating and servicing.
2 . 1 . 5 C O M B I N A T I O N L O W W A T E R C U T - O F F &
F E E D E R
The low water cut-off/feeder supplied with some boilers serves as a low water cut-off (see above)
and also causes make-up water to be added to the boiler, should the water level drop below its
control point. This type of control must be operationally tested as described in Section 2.1.1 and
also to assure that the make-up water is introduced as needed. Carefully read the enclosed
literature on the Low Water Cut-off controls, particularly installing, operating and servicing
.
2 . 1 . 6 O T H E R C O N T R O L S
Additional controls, as required for the particular installation, may also be provided. Refer to the
literature on these devices included in the Boiler Manual. All such devices must be operationally
tested to assure reliable operation of the boiler and system.
2 . 1 . 7 B O I L E R F E E D S Y S T E M
The boiler feed pump must be operationally tested to assure that it can provide boiler feedwater at
the pressure and in the amount needed for safe and reliable boiler operation.