LCD Series Finned Copper Tube Gas Boilers & Water Heaters – Boiler Manual
32
Pilot Adjustment
The pilot burner is actually an isolated main burner that’s
controlled by a separate pilot valve. Pilot pressure settings are as
shown in Table 20. These pressures are measured at the pilot pressure
valve, see Figure 19. Tables 13 and 14 above list the firing mode
that is associated with each stage.
To view the pilot without main burner operation, take the following
steps:
For 400:
1. Remove the upper front jacket panel.
2. Turn off main burner gas flow by turning the main burner gas
valve knob to the off position, Figure 18.
3. Observe the pilot flame through one of the observation ports
located at the left and right ends of the unit.
For 600-2300:
1. Remove the upper front jacket panel.
2. Turn off main burner gas flow by turning the manual gas valve(s)
in the control compartment to the off position, see Figure 19.
3. Observe the pilot flame through one of the observation ports
located at the left and right ends 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 20, take the
following steps:
1. Remove the upper front jacket panel.
2. Remove the 1/8 in plug from the pilot pressure test port and
connect a
20 in
,
508 mm
WC 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.
4. Use a 3/32 hex wrench to turn the pressure regulator adjustment
screw clockwise to increase the pilot pressure and counter
clockwise to decrease it.
5. Replace the pressure regulator adjustment screw cap.
Gas Pressure Adjustment
The maximum inlet gas pressure listed on the rating
plate must not be exceeded or damage to the boiler/
water heater may occur voiding the warranty!
The minimum supply pressure listed on the rating plate is for input
adjustment.
The manifold pressures should match those listed in Table 20.
Pressures should not vary outside these ranges. Each gas valve
pressure regulator has been preset at the factory. If neccessary, adjust
the gas pressures to achieve the combustion results show in Table
21.
If adjustments are necessary the following steps must be followed:
1. Remove the 1/8 in plug from the manifold pressure tap valve.
Connect
20 in
,
508 mm
WC manometers to it, see Figure 19.
2. Remove the regulator adjustment screw cap from the main gas
valve.
3. Rotate the regulator adjustment screw clockwise to increase the
manifold pressure, counter clockwise to decrease it.
4. Replace the regulator adjustment screw cap and manual shut
off valve pressure tap plug.
Never force the regulator adjustment screw beyond
the stop limits or damage to the regulator will occur!
PROPANE GAS: Optimum results are obtained when the
boiler/water heater is operated with the manifold pressure(s) set
per Table 20. If the manifold pressure is off by more than 5% adjust
it according to steps 1 through 4 above.
Airflow Adjustment
1. Remove the upper front jacket panel.
2. Connect both sides of a manometer to the pressure switch tee,
Figure 17, going to one of the pressure switches.
3. With the unit operating at high fire the differential pressure should
match those listed in Table 15. Do not change air pressure in
lower stages.
