74
e. If low fire O
2
is too low (CO
2
is too high),
increase O
2
(decrease CO
2
) by turning offset
screw counterclockwise in less than 1/8 turn
increments and checking the O
2
(or CO
2
)
after each adjustment. If boiler is equipped
with 2 gas valves, offset screw adjustments
must be done to both gas valves equally and
simultaneously. Refer to Figure 50 for location
of offset screw. Verify CO air free is less than
200 ppm.
f. If low fire O
2
is too high (CO
2
is too low),
decrease O
2
(increase CO
2
) by turning
offset screw clockwise in less than 1/8 turn
increments and checking the O
2
(or CO
2
)
after each adjustment. If boiler is equipped
with 2 gas valves, offset screw adjustments
must be done to both gas valves equally and
simultaneously. Refer to Figure 50 for location
of offset screw. Verify CO air free is less than
200 ppm.
iX. System Start-up
(continued)
Warning
Make sure that all adjustments at high fire are
made with the throttle, not offset screw (see
Figure 50). The offset screw has been factory set
using precision instruments and must never be
adjusted in the field unnecessarily.
attempting to adjust the offset screw
unnecessary could result in damage to the gas
valve and may cause property damage, personal
injury or loss of life.
b. If high fire O
2
is too low (CO
2
is too high),
increase O
2
(decrease CO
2
) by turning the throttle
screw clockwise in 1/4 turn increments and
checking the O
2
(or CO
2
) after each adjustment.
If boiler is equipped with 2 gas valves, throttle
screw adjustments must be done to both gas
valves equally and simultaneously. Refer to
Figure 50 for location of throttle screw. Verify
CO air free is less than 200 ppm.
c. If high fire O
2
is too high (CO
2
is too low),
decrease O
2
(increase CO
2
) by turning the
throttle screw counter-clockwise in 1/4 turn
increments and checking the O
2
(or CO
2
)
after each adjustment. If boiler is equipped
with 2 gas valves, throttle screw adjustments
must be done to both gas valves equally and
simultaneously. Refer to Figure 50 for location
of throttle screw. Verify CO air free is less than
200 ppm.
d. Lock boiler in low fire and allow fan speed and
combustion analyzer reading to stabilize before
taking combustion readings. Press “Low” to
lock boiler in low fire.
Warning
asphyxiation Hazard. Offset screw is adjusted
at the factory to the specification. DO NOT
touch the offset screw if measured low fire O
2
(or CO
2
) is within limits specified in Table 35 or
36.
Figure 50: gas Valve Detail
3. Remove analyzer probe
and replace cap on
boiler vent connector.
4. Return boiler to Automatic Mode.
Press
“Auto”.
P. Test Safety Limits Controls
1. Test the ignition system safety shut-off
by
disconnecting the flame sensor connector (black
plug with orange wire) from the flame ionization
electrode. See Figure 40. The boiler must shut
down and must not start with the flame sensor
disconnected.
Figure 49: Burner Flame
Summary of Contents for Alpine ALP500C
Page 48: ...48 VI Water Piping and Trim continued Figure 28 Near Boiler Piping Heating Only ...
Page 62: ...62 Figure 40 Ladder Diagram VIII Electrical continued ...
Page 63: ...63 VIII Electrical continued 2 Figure 41 Wiring Connections Diagram ...
Page 72: ...72 IX System Start up continued Figure 48 Operating Instructions ...
Page 124: ...124 XIII Repair Parts continued ...
Page 126: ...126 XIII Repair Parts continued ALP600C ALP700C and ALP800C ALP800C shown ...
Page 130: ...130 XIII Repair Parts continued ...
Page 133: ...133 XIII Repair Parts continued 10A 10B 10C 10D 10G ...
Page 143: ...143 ...
Page 144: ...144 U S Boiler Company Inc P O Box 3020 Lancaster PA 17604 1 888 432 8887 www usboiler net ...
