Installation Guide

20
VIII. Operation
A. BOILER SEQUENCE OF OPERATION
NORMAL OPERATION
1. The RRG Series Boilers are equipped with an
Integrated Boiler Control (IBC). This IBC replaces
the traditional separate ignition control, high limit
switch and circulator relay and adds energy saving
thermal purge features. Energy is saved by starting
the circulator and delaying the burner start when
there is residual heat available in the boiler.
2. The boiler’s sequence of operation is shown in
Table 3.
3. When the thermostat calls for central heat (CH) the
IBC starts the system circulator and the thermal
purge begins. If the boiler temperature is less than
140°F, the start sequence continues by energizing
the vent damper. Once the vent damper is fully
open the ignition sequence is started allowing gas
 ow and ignition of the burners. Damper must be
in open position when appliance main burners are
operating.
4. If the call for CH is not satis ed and the operating
setpoint is reached the system circulator will
continue to operate and the burners will stop.
When the boiler water temperature drops below the
setpoint less the differential setting the burners will
restart.
5. After the call for CH is satis ed the burners and
circulator are stopped and vent damper is closed.
6. When the Domestic Hot Water (DHW) calls for
heat, the control starts the circulator and, if the
boiler temperature is less than the operating setpoint
less differential, the vent damper is energized
without delay. Once the vent damper is fully open,
the ignition sequence is started allowing gas  ow
and ignition of the burners.
The default DHW high limit is 200°F. The DHW
high limit will match CH set point if CH set point is
below 200°F.
B. BOILER FAULT
In the event the boiler fails to start, the control provides
status information to help determine the cause of the
problem. Table 4 from Section X: Troubleshooting
(page 24) provides a list of boiler  ash codes indicating
the source of the lockout. Refer to the Troubleshooting
Section for more information.
Status POWER TSTAT/CIRC LIMIT DAMPER FLAME
1 Standby
    
2 Call for heat - Circulator on
    
3 Limit circuit closed
    
4 Vent Damper - Proven open
    
5 Pilot  ame proven
    
Figure 17: Integrated Boiler Control
C. USING DISPLAY AND ADJUSTMENT KNOBS
The control is located inside the boiler. (Figure 17).
The IBC display, along with two adjustment knobs may
be used to change two parameters. The status LEDs are
located to the right of the display. When powered the
POWER LED is green and the remaining LEDs will
light up red depending on the state of the control (see
Figure 18).
1. High limit setpoint
The High Limit Setpoint is user adjustable by
turning the top knob labeled “BOILER TEMP”.
Adjustment range is 140°F to 220°F. During
normal operation the LED display will show
 - LED illuminated
 - LED off
Table 3: Sequence of Operation Using the Controls LEDs