Laars NeoTherm NTH Installation and operation instructions manual - page 29
NeoTherm Boiler
Page 29
6.2.2 Boiler Setup and Adjustment
1.
Connect a manometer capable of reading -.005"wc
to the gas valve locations shown in
Figure 22
. The
positive side of the manometer should be
connected to the location labeled “air pressure
tap.” The negative side of the manometer should
be connected to the location labeled "gas pressure
tap." This differential pressure should be slightly
negative (see
Table 13
).
2.
Measure the CO
2
/O
2
in the flue products at high
fire. The NeoTherm can be forced to high fire to
allow for easier setup. Refer to Section 5.2.3 for
instructions on how to access the forced rate menu.
The CO
2
readings should be between the values
shown in
Table 13
. If the CO
2
is not within the
range shown, adjustments may be made. To adjust
the high fire CO
2
, locate the high fire adjuster
screw according to the appropriate figure. Slowly
make adjustments in 1/16 of a revolution
increments until the CO
2
is within the range
identified.
NOTE: NeoTherm 399 does not have a high fire
adjustment.
3.
Measure the CO
2
/O
2
in the flue products at low
fire. The NeoTherm can be forced to low fire to
allow for easier setup. Refer to
Section 5.2.3
for
instructions on how to access the forced rate menu.
The CO
2
readings should be between the values
shown in
Table 13
. If the CO
2
is not within the
range shown, adjustments may be made. To adjust
the low fire CO
2
, locate the low fire adjuster screw
according to the appropriate figure. Slowly make
adjustments in 1/16 of a revolution increments
until the CO
2
is within the range identified.
4.
Repeat steps 2 and 3 to confirm that the CO
2
ranges are within the required ranges. Adjust if
necessary.
5.
Confirm that the differential pressure is still within
the appropriate range.
6.
If any of the measurements cannot be adjusted to
the specified ranges or the CO levels are above
150ppm when adjusted please consult the factory
for further information.
7.
Remove the differential pressure gauge from the
air and gas pressure taps making sure to close all
ports after the gauge has been removed.
WARNING
Improper adjustment may lead to poor combustion
quality, increasing the amount of carbon monoxide
produced. Excessive carbon monoxide levels may
lead to personal injury or death.
6.3 Shutting Down the NeoTherm
1.
Turn off the main electrical disconnect switch.
2.
Close all manual gas valves.
3.
If freezing is anticipated, drain the NeoTherm and
be sure to also protect building piping from
freezing. All water must be removed from heat
exchanger or damage from freezing may occur.
This step to be performed by a qualified service person.
6.4 To Restart the NeoTherm
If drained, follow
Section 6.1
in this manual for
proper filling and purging.
1.
Turn off the main electrical disconnect switch.
2.
Close all manual gas valves.
3.
WAIT FIVE (5) MINUTES.
4.
Set the aquastat or thermostat to its lowest setting.
5.
Open all manual gas valves.
6.
Reset all safety switches (pressure switch, manual
reset high limit, etc.).
7.
Set the temperature controller to the desired
temperature setting and switch on electrical power.
8.
Burner will go through a prepurge period and
ignitor warm-up period, followed by ignition.