Watts AERCO Benchmark BMK750 Operation And Service Manual page 58

Benchmark with Edge [I]: Operation-Maintenance Manual
SECTION 4 – INITIAL START-UP
NATURAL GAS Manual Combustion Calibration Instructions
16. With the valve position still at 100%, insert the combustion analyzer probe into the exhaust
manifold probe opening (see Figure 4-2a – 4-2c in Section 4.2.3) and allow enough time
for the combustion analyzer reading to stabilize.
17. Compare the combustion analyzer's oxygen (O
column (Figure 4-6). If they differ, go to the
Oxygen Sensor
board O sensor match the value from the combustion analyzer. If your combustion
2
analyzer is correctly calibrated, and the on-board O
analyzer, the sensor may be defective and need to be replaced.
18. Compare the O
2
Blower Voltage until the O
or press on the field and type the value directly.
19. If adjusting the blower voltage is not sufficient to get the O
Target column, then repeat Step 15 to adjust the gas pressure up or down within the range
shown in the table, then repeat Step 18. Continue repeating Steps 15 and 18 until the gas
pressure is within the range in Table 4-1 and the O
Target column.
20. Enter the downstream manometer's gas pressure reading in the Downstream Gas
Pressure field. Note, this field appears only when Valve Position % = 100%.
21. Compare the measured nitrogen oxide (NOx) and carbon monoxide (CO) readings to the
Target values (shown in Table 4-2 as a reference only). If you chose the NOx <=9 ppm in
step 9, use the values in the Ultra-Low NOx columns. If you are not in a "NOx-limited"
area and/or do not have a NOx measurement in your analyzer, set the O
the Standard NOx column in the table below.
TABLE 4-2: NATURAL GAS Calibration Target Values @ 100% Valve Position
Model
750 5.5% ± 0.2%
1000 5.5% ± 0.2%
1500 5.2% ± 0.2%
2000 6.0% ± 0.2%
2500 5.6% ± 0.2%
3000 5.1% ± 0.2%
3000 DF 5.3% ± 0.2%
4000 5.5% ± 0.2%
5000/6000 5.5% ± 0.5%
NOTE:
These instructions assume that the inlet air temperature is between 50°F and 100°F
(10°C – 37.8°C). If NOx readings exceed the target values in Table 4-1, above, or Table 4-
3, below, increase the O
the increased O value on the Combustion Calibration sheet.
2
22. On Benchmark 3000 - 6000 units only, record the manifold (downstream) gas pressure at
100%. This value will be used in Section 5.2.2: Low Pressure Gas Test, and Section 5.3.2:
High Pressure Gas Test.
OMM-0145_A99 • GF-218 •
screen and adjust the O2 Offset parameter, up to ±3%, to make the on-
value in the Target and Reading columns. If they don't match, adjust the
value in both columns match; use either the + or – controls,
2
Standard NOx
O % NOx
2
≤20 ppm
≤20 ppm
≤20 ppm
≤20 ppm
≤20 ppm
≤20 ppm
≤20 ppm
≤20 ppm
≤20 ppm
level up to 1% higher than the Target value. You must then record
2
Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST
9/18/2019
) reading to the O
2 2
Main Menu → Calibration → Input/Output →
sensor cannot be made to match the
2
Reading column to match the
2
Reading column to matches the
2
Ultra-Low NOx
O % NOx
2
≤9 ppm
6.0% ± 1.0%
≤9 ppm
6.0% ± 1.0%
≤9 ppm
5.7% ± 1.0%
≤9 ppm
6.0% ± 1.0%
- -
- -
- -
≤9 ppm
6.0% ± 0.2%
≤9 ppm
6.0% ± 1.0%
value in the Reading
to the value in
2
CO
<100 ppm
<100 ppm
<100 ppm
<100 ppm
<100 ppm
<100 ppm
<100 ppm
<100 ppm
<100 ppm
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