Boiler/Water Heater Operation - RBI DOMINATOR Series Installation And Operation Manual

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Start the boiler as described in the "OPERATING
INSTRUCTIONS". Run the boiler for at least an hour.
The system pump(s) and all radiation units must be
operated during this time. Ensure that the make-up
water valve is open.
Shut the boiler off and open the bleed valves to purge
the air trapped in the heating system piping. Close the
make-up water valve and check and clean the strainers
and make-up water pressure reducing valve.
Open the make-up water valve and adjust the system
pressure if necessary. The system should be checked
and bled after three days of operation.
BOILER/WATER HEATER
OPERATION
Staging Operation
The Dominator boiler/water heater series is separated
into 2-stage and 4-stage units depending on the model
size. The 300 through 2100 models have two fi ring inputs.
The 1050 through 2100 have four. Input staging is
controlled from the staging controller that signals the
relay board to select the blower and gas valve modes.
Table 12 identifies the stages and firing modes
associated with the 2 stage units (D300-D2100), and
Table 13 identifies the stages and firing modes
associated with the 4 stage units (D1050-D2100).
Table 12 - Firing Modes (D300-D2100)
Stage Firing Mode
Off
1
2
Table 13 - Firing Modes (D1050-D2100)
Stage Left Firing Mode
Off
1
2
3
4
1-The left main valve will operate at low fi re, but left and right
blowers will be on and operating at low fi re (low speed).
The outlet water temperature is automatically controlled
by the staging controller. It utilizes inputs from the inlet
and outlet water temperature sensors, plus optional tank
and outside sensors, to stage the boiler/water heater.
The Dominator will stage up or down progressively, but
will not jump over a stage. Stage 1 will operate fi rst, last
and whenever the boiler/water heater is in operation.
Consult the staging controller documentation for further
information on controller operation.
DOMINATOR INSTALLATION AND OPERATION INSTRUCTIONS
Off
Low Fire
High Fire
Right Firing Mode
Off Off
Low Fire Off
Low Fire Low Fire
High Fire Low Fire
High Fire High Fire
For the D1050-D2100, the air inlet plenum is divided into
left and right sides. A separate blower, main gas valve
and manifold are used for each side. However, the
combustion chamber is undivided. For best overall
performance, gas and airfl ows should be balanced so
that when both sides are at low or high fi re, stage 2 or
4, the gas and airfl ows are equal.
Pressure Switch Settings
Differential pressure switches are provided in the
Dominator to shut down gas fl ow under a blocked fl ue
or inlet condition. One low fi re and one high fi re pressure
switch are used for the 300 through 900 models. Two
low fi re and two high fi re pressure switches are used
for the 1050 through 2100 models. The low fi re pressure
switches serve to shut down gas flow if there is a
blocked fl ue or inlet condition during low fi re operation.
Similarly, the high fi re switches will shut down gas fl ow
if there is a blocked fl ue or inlet condition during high
fire operation. The differential pressure is taken
between the air plenum and the pressure inside one
of the main burners.
Pressure taps are provided in the control compartment
for taking the differential pressure readings, Figure 17.
Table 14 lists the differential pressure settings for all of
the models.
Figure 17 - Pressure Switch Tap(s)
1
Table 14 - Differential Pressure Settings (All Units)
Model
300-900
1050-2100
RIOM-
Differential Pressure
Requirement at High Fire
(All Units)
Inches W.C. mm W.C.
0.80 ± 0.1 20.3 ± 2.5
0.90 ± 0.1 22.9 ± 2.5