69
WHL-032 REV. 6.2.16
5. The minimum and maximum inlet gas line pressures must meet the requirements shown in Table 28.
LP GAS
NATURAL GAS
Minimum Pressure
3.5” WC
Minimum Pressure
3.5” WC
Maximum Pressure
14” WC
Maximum Pressure
14” WC
Table 29
– Gas Pressure Requirements
6. Remove the manometer. Close the screw on the gas inlet pressure tap.
J. SETTING AND VERIFYING THE COMBUSTION SETTING
1. After the boiler has fired, flip DIP switch seven (7) to the ON position (low fire). Proceed to check boiler combustion values.
NOTE:
Use a combustion analyzer to ensure CO and CO
2
values are within the range shown in Table 28.
It is required to use a combustion analyzer to verify final adjustment according to the combustion chart (Table 29). Failure to do so
could result in serious personal injury or death.
If the readings obtained are lower or higher than the combustion readings in Table 29, use a 4mm Allen key to adjust the offset screw in
a clockwise (positive) or counterclockwise (negative) direction (approximately 1/4 turn). See Figure 57. Check your combustion values.
Repeat this procedure until the values obtained on the combustion analyzer agree with those stated in Table 29.
NOTE:
If the boiler makes a whistling sound (harmonics) at low fire, adjust the offset screw in a clockwise (positive) direction
(approximately 1/8 turn). Check your combustion values and ensure they agree with those stated in Table 29 before proceeding.
It is very important that the installation be set within the recommended CO measurements listed in Table 29. Visually looking at the
burner does not determine combustion quality. Failure to measure combustion with a Combustion Analyzer and set the throttle within
the recommended CO measurements could result in property damage, severe personal injury, or death.
COMBUSTION SETTINGS
Figure 57
– Gas Valve Offset Screw
NATURAL GAS
LP GAS
FAN SPEED
LOW
HIGH
LOW
HIGH
CO PPM
<175
<175
<175
<175
CO
2
(%)
8
– 9 ½
8 ½ - 10
9
– 10 ½
9 ½ - 11
Table 30
– Combustion Settings
2. When low fire settings have been obtained, flip DIP switch seven (7) to its original (OFF) position. This will return the boiler to normal
mode.
3. Flip DIP switch six (6) to ON (high fire). Again check combustion readings with a combustion analyzer.
4. When complete, flip DIP switch six (6) to its original (OFF) position. This will return the boiler to normal mode.
5. Allow boiler to operate normally. Ensure it is operating properly.
6. Reinstall the boiler front cover.
7. Use a Phillips Head screwdriver to reinstall the boiler top cover.
