Laars NTH1000, Installation And Operation Instructions Manual

Page: 78 / 140

LAARS Heating Systems Page 74
9. You can change the fan speed of the burner
by adjusting the value entered for Firing Rate
on the right side of the display. (Remember, a
moment ago you selected the Primary control
for this boiler, so this change will only affect
the Primary burner.) Press the yellow box
beside the Firing Rate label.
10. The system will ask you to log in using a
password. Enter the installer-level password,
then press OK.
11. Press the box for Firing Rate again. The
controller will present the Manual Firing Rate
screen shown in Fig. 104.
Fig. 104 - Manual Firing Rate
12. Notice the three options on the left side of the
screen:
Auto -
The firing rate will be set automatically by
the controller, based on the heat load. Set this
item to Auto at the end of the test.
Manual in Run -
The Manual in Run control will only set the
fan speed when the control has proven flame
and the unit has entered the Run mode.
Manual in Run and Standby -
Using this setting, the manual control will set
the fan speed whether the boiler is operating
or not.
For this test, select Manual in Run.
13. Type in a value for high fire RPM. Enter 8000
RPM. (The actual RPM will not go this high
– the control will limit the fan speed to the
maximum set at the factory.)
By using the manual control, and entering a
high RPM value, this forces the burner to run
at full combustion so you can adjust the gas
valve for the correct CO
2
output.
Figures 105 and 106 show the adjusting points
on the gas valve. Adjust the High Fire screw
to get the proper CO
2
level for high fire. See
Table 17. To raise the high fire CO
2
level,
Fig. 105 – Connections for
Pressure Gauge - NT 1000
Positive connection point
Negative connection point
Fig. 106 – Connections for
Pressure Gauge - NT 1700
Negative
connection
point
Positive
connection
point