70
6. After the burner lights, force the burner to high re
by simultaneously pressing and holding the “Mode”
button and “+“ button. After a few seconds, the
display should ash “H”, indicating that the boiler
has been driven to high re. Allow the boiler to
operate for approximately 5 minutes before taking
combustion readings. Note: after 15 minutes, the
boiler is automatically released from high re hold.
Be sure to restore high re hold if additional time is
needed to obtain high re combustion readings.
Figure 48: Dungs gas Valve Detail
7. Perform a combustion test. Boilers equipped with a
concentric vent system have a ue gas sample tap
located in the boiler vent collar (under the screw
cap).
8. While the burner is at high re adjust the throttle as
needed to obtain the CO2 (or O2) settings shown in
the Table 23:
• To reduce the CO2 (increase the O2) turn the
throttle clockwise
• To increase the CO2 (reduce the O2) turn the
throttle counter-clockwise
Make adjustments in increments of 1/8 to 1/4 turn
and allow the boiler at least a minute to respond to
each adjustment before making another. In general,
the CO level will be at its lowest somewhere in the
CO2 range shown in this table.
Boiler
Model
Altitude Range
0 - 7000 Ft.
% CO2 % O2 Range CO, PPM
ALP080
9.5 - 10.1 5.5 - 6.5 Less than
75 PPM
ALP105
ALP150
ALP210
ALP285
ALP399
Table 23: Recommended Combustion Settings,
LP gas
9. Verify that the gas inlet pressure is between the
upper and lower limits shown in Table 24 with all
gas appliances (including the converted boiler) both
on and off:
10. A label sheet is provided with the boiler for
conversions from natural to LP gas. Once conversion
is completed, apply labels as follows:
• Apply the “Rating Plate Label” adjacent to the
rating plate.
• Apply the “Gas Valve Label” to a conspicuous
area on the gas valve.
WaRning
The pressure regulator has been factory set using precision instruments and must never be adjusted in
the eld. The gas valve outlet pressure is the same for both natural gas and propane. Make sure that
all adjustments are made with the throttle, not the pressure regulator. attempting to adjust the pressure
regulator will result in damage to the gas valve and may cause property damage, personal injury or loss of
life.