DOMINATOR INSTALLATION AND OPERATION INSTRUCTIONS
Page 30
CHECKING & ADJUSTMENTS
1. With the burners in operation, close the manual
shutoff valve in the gas supply line. As soon as the
main burner fl ames go out, open the manual shutoff
valve. A normal ignition sequence should take place.
If the burners fail to light, the gas valves will close
and the system will go into a 5-minute lock out
period. The ignition module will then make a second
ignition attempt. If the unit won't light ensure that the
gas piping is fully purged of air. Inspect the ignition
system and ensure that it is operating properly.
2. To test the ignition safety shutoff device, close the
manual shutoff valve in the gas supply line. Within 5
seconds of main burner fl ame extinction, the main
gas valve solenoid should close with an audible noise.
The pilot light on the display board should be lit while
the ignition module tries to relight the pilot. After 10
seconds the module should lockout and the trial for
ignition end. After 5 minutes a second trial for ignition
should occur. Open the manual shutoff valve in the
gas supply line and reset the ignition control system.
A normal ignition sequence should take place.
3. With the burners in operation, interrupt the power to
the control circuit by reducing the target temperature
of the staging controller or turning down the
thermostat. The boiler/water heater should stage
down and shut down. Reset the operating control or
thermostat. A normal ignition sequence should follow.
Input Rate, Natural Gas
Gas appliances are rated based on sea level operation
with no adjustment required at elevations up to
5000 ft
,
1524 m
. At elevations above
5000 ft
,
1524 m
, input
ratings should be reduced by 4% for each additional
1000 ft
,
305
m
.
Check the input rate as follows:
1. Turn off all other gas appliances that use the same
gas meter as the boiler/water heater.
2. Call your gas supplier and ask for the heating value
of the gas.
3. Connect a fl ue gas analyzer to the vent pipe.
4. Start the boiler/water heater and let it run for 15
minutes.
5. Using the gas meter and a stopwatch, clock the time
that it takes to burn
10 ft
3
,
0.28 m
3
of gas and divide
this time by 10.
6. Insert the heating value and the time, in seconds,
into the formula below.
7. Input = (heating value, Btu/hr)(3600)/(time, seconds)
8. If the computed rate deviates by more than 5% from
the rated input value of the unit adjust the manifold
pressure accordingly. DO NOT adjust the manifold
pressure by more than 5%. If a proper rate cannot
be maintained without adjusting the manifold
pressure beyond the 5% limit, the main burner
orifi ces must be replaced. If the input rate is too low,
go to the next larger size of main burner orifi ces. If
the input rate is too high, go to the next smaller size.
9.
At full input the CO
2
should be between 7.5%
and 8.5% with a CO reading of less than 50 ppm.
See Table 20.
CAUTION: Never increase the input of the boiler/
water heater above that for which it is rated. Doing
so can cause premature failure of the unit!
Pilot Adjustment
The pilot burner is actually an isolated main burner that
stages with the other burners. It is controlled by a
separate pilot valve. Pilot pressure settings are as shown
in Table 19. These pressures are measured at the pilot
pressure valve, see Figure 19. See Tables 12 and 13 to
determine the fi ring mode that is associated with each
stage.
To view the pilot without main burner operation, take the
following steps:
For D300-D400:
1. Remove the upper front jacket panel.
2. Turn off main burner gas fl ow by turning the main
burner gas valve knob to the off position, Figure 18.
3. Observe the pilot fl ame through the observation port
located at the left end of the unit.
For D600-D2100:
1. Remove the upper front jacket panel.
2. Turn off main burner gas fl ow by turning the manual
gas valve(s) in the control compartment to the off
position, see Figure 19.
3. Observe the pilot fl ame through the observation port
located at the left end of the unit.
Pilot pressures will be set at the factory. However, if it
is necessary to adjust the pilot pressure to match those
in Table 19, take the following steps:
1. Remove the upper front jacket panel.
2. Remove the 1/8" plug from the pilot pressure test
port and connect a
20 in
,
508 mm
W.C. manometer
to it, see Figure 18.
3. Remove the gas pressure regulator cap from the
pilot valve. See Figure 18 for the location of the
regulator and cap.
