USER’S INFORMATION MANUAL
PAGE 2
BASIC OPERATION
A. General.
This water boiler is a natural draft appliance
and is equipped with controls for proper operation. All
controls must be in proper working order. Contact a
qualified service agency to provide annual mainten-
ance as specified in the Installation, Operation and
Maintenance Manual.
B. Control Locations.
See Figure 1 for Control and
Safety Device Locations.
1a.
Limit (Steam Boiler).
An electrical device that
automatically interrupts the boiler operation
when the steam pressure exceeds the “CUT IN”
pressure plus the differential (1 to 5 psi).
Maximum Pressure setting is 14 psig. The set
point is usually less than 5 psig.
Original equipment with this boiler is a Honey-
well PA404A1009. Boiler operation is
interrupted when the steam pressure exceeds
the the “CUT IN” pressure plus the differential.
Boiler opera-tion resumes automatically when
the system pres-sure falls below the “CUT IN”
pressure.
1b. Limit Control may incorporate a low water cut-
off feature that will interrupt boiler operation
upon loss of water in the boiler. If the low water
cut-off function is activated to interrupt boiler
operation, follow the instructions TO TURN
OFF GAS TO THE APPLIANCE (see Figures
3-5) and contact a qualified service agency.
2.
Flame Rollout Switch (FRS).
An electrical
device that automatically interrupts the boiler
operation when excessive heat is present in
the combustion area. The control is a thermal
fuse device that will require replacement if it
is activated. If the control has been activated
to interrupt the boiler operation, do not attempt
to restart the boiler. Contact a qualified service
agency.
3.
Blocked Vent Switch (BVS)
An electrical
device that automatically interrupts the boiler
operation when there is a blockage in the vent
pipe or chimney. The control is located on the
side of the draft hood and is a manual reset
device. If the control is activated to interrupt
operation of the boiler, do not attempt to restart
the boiler. Contact a qualified service agency.
4.
Pilot.
The pilot provides an ignition source for
the main burners. Your boiler has an
intermittent (spark ignited) pilot. The
intermittent pilot ignites only when there is a call
for heat and extinguishes when the call for heat
ends. See Figure 6.
5.
Gas Valve.
The gas valve monitors pilot flame
and regulates gas flow to the burners and pilot.
WARNING
Service on this boiler should be undertaken only
by trained and skilled personnel from a qualified
service agency.
CAUTION
Should overheating occur or the gas supply fail
to shut off, turn off the gas supply at a location
external to the appliance.
Do not use this boiler if any part has been under
water. Immediately call a qualified service agency
to inspect the boiler and to replace any part of the
control system and any gas control which has
been under water.
Figure 1: Control Location
