Bryan Boilers Forced Draft Steam Boilers - Manual (Page 22)

START-UP AND OPERATION
STEAM BOILERS
WARNING:
IMPROPER SERVICING AND START-UP OF THIS EQUIPMENT MAY CREATE A
POTENTIAL HAZARD TO EQUIPMENT AND TO OPERATORS OR PERSONS IN THE
BUILDING.
SERVICING AND START-UP MUST BE DONE ONLY BY FULLY TRAINED AND
QUALIFIED PERSONNEL.
CAUTION:
BEFORE DISCONNECTING OR OPENING ANY FUEL LINE, OR BEFORE CLEANING OR REPLACING
PARTS OF ANY KIND, TAKE THE FOLLOWING PRECAUTIONS:
Turn OFF the main fuel shutoff valves, including the pilot gas cock if applicable. If the burner is a multiple
fuel type, shut OFF all fuel supplies.
Turn OFF all electrical disconnects to the burner, boiler and any other equipment or systems electrically
interlocked with the burner or boiler.
All cover plates, enclosures, and guards must be in place at all times except during maintenance and
servicing.
2.1 FIRING RATE ADJUSTMENT - ATMOSPHERIC GAS UNITS
2.1.1 The following procedures must be followed
carefully before putting the boiler in operation.
Failure to do so will present severe hazards to
equipment, operating personnel and building
occupants.
2.1.2 ADJUST PILOT BURNER
Carefully follow the Lighting Instructions in the
boiler manual for the proper adjustment of the
pilot burner. This is absolutely essential before
attempting to adjust the main burner.
2.1.3 ADJUST BOILER INPUT(S)
The boiler input must be adjusted for both
maximum and minimum input values which are
listed on the boiler nameplate. First adjust the
maximum input rating using the method
described in Lighting Instructions in the Boiler
Manual. Refer to the following information for the
adjustment of the minimum input. To determine
the adjustment
which firing rate system is used, see the boiler
Equipment List and Wiring Diagram.
2.1.4 ADJUST BOILER MINIMUM INPUT
After setting the correct Maximum input as
described in the Lighting Instructions, proceed to
adjust the minimum input as outlined below. This
applies only to those boilers which are designed
and equipped for two-stage (High/Low/Off) firing
or Modulation. On those boilers which are
equipped for ON/OFF firing only, no minimum
input adjustment is required. NOTE: the low firing
rate input is adjustable only on boilers equipped
with two-stage or modulating motorized gas
valves (V4055, V9055, or AH4 actuators) or with
motor-operated modulating butterfly gas valves.
The other two-stage firing systems (VR850 or
VR852 combination valves or dual diaphragm
valve type bypass systems) have a non-
adjustable minimum input rate.