BASIC OPERATION
A. General. This water boiler is a natural draft appli-
ance and is equipped with controls for proper opera-
tion. All controls must be in proper working order.
Contact a qualified service agency to provide annual
maintenance as specified in Installation, Operation
and Maintenance Manual.
1.
Limit. See Figure 1. A device which automati-
cally interrupts boiler operation when the water
temperature exceeds the set point. Maximum
allowable temperature is 240°F (115°C).
Original equipment with this boiler is a
Honeywell L8148E1182. Boiler operation is
interrupted when system temperature reaches
cut-out temperature. Boiler operation resumes
automatically when system temperature falls
approximately 15°F (8°C) below the cut-out
temperature. See also Figures 4 and 5 for limit
sequence of operation.
2.
Flame Rollout Switch. See Figure 1. A device
which automatically interrupts boiler operation
when flames or excessive heat are present in
the combustion area. The control is a single use
device. If the control is activated to interrupt
boiler operation, do not attempt to place boiler in
operation. Contact a qualified service agency.
3.
Blocked Vent Switch (Vent Safety Shutoff
Switch). See Figure 1. A device which auto-
matically interrupts boiler operation when there
is a blockage in the vent pipe or chimney. The
control is a manual reset device. The control is
located on the draft hood relief opening. If the
control was activated to interrupt boiler opera-
tion, do not attempt to place boiler in operation.
Contact a qualified service agency.
4.
Pilot. The pilot provides the ignition source for
the main burners. Your boiler has a standing
(continuous) pilot or an intermittent pilot. The
intermittent pilot ignites only when there is a call
for heat and extinguishes when the call for heat
ends. See Figures 6 and 7.
5.
Gas Valve. The gas valve monitors pilot flame
and regulates gas flow to the burners and pilot.
See Figure 1.
6.
Safety Relief Valve. A device which protects
the boiler against excessive pressure. The safe-
ty relief valve can discharge a large amount of
hot water - the installer should provide piping to
discharge water near floor at a floor drain. If the
safety relief valve discharges water, follow
instructions TO TURN OFF GAS TO APPLI-
ANCE (see Figure 2 or 3), and contact a quali-
fied service agency.
Figure 1: Control Locations
B. Instructions to place boiler in operation and to turn
off the boiler are shown on the Operating or Lighting
Instruction Label posted on the left side of the boiler.
The instructions are also shown in Figures 2 and 3.
C. The Sequence of Operation is shown in Figures 4
and 5.
WARNING
CAUTION
Service on this boiler should be undertaken only
by trained and skilled personnel from a qualified
service agency.
Should overheating occur or the gas supply fail
to shut off, do not turn off or disconnect the
electrical supply to the pump. Instead, shut 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.
HWX USER’S INFORMATION MANUAL
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