Bmk 2000 Natural Gas Combustion Calibration - Benchmark BMK 1500 User Manual

BMK 2000 Natural Gas Combustion Calibration

4.3.2
1. Open the water supply and return valves to the unit and ensure that the system pumps
are running.
2. Open the natural gas supply valve to the unit.
3. Set the control panel ON/OFF switch to the OFF position
4. Turn on external ac power to the unit. The display will show loss of power and the time
and date.
5. Set the unit to the manual mode by pressing the AUTO/MAN key. A flashing manual
valve position message will be displayed with the present position in %. Also, the
MANUAL LED will light.
6. Adjust the air/fuel valve position to 0% by pressing the ▼ arrow key.
7. Ensure that the leak detection ball valve downstream of the SSOV is open.
8. Set the ON/OFF switch to the ON position.
9. Change the valve position to 30% using the ▲ arrow key. The unit should begin its start
sequence and fire.
10. Next, verify that the gas pressure downstream of the SSOV is set to 3.9 ± 0.2" W.C. If
gas pressure adjustment is required, remove the brass hex nut on the SSOV actuator to
access the gas pressure adjustment screw (Figure 4-3). Make gas pressure adjustments
using a flat-tip screwdriver to obtain a gas pressure within the range of 3.9" W.C. ± 0.2"
W.C.
11. Using the ▲ arrow key, increase the valve open position to 100%. Verify that the gas
pressure on the downstream side of the SSOV settles within the range of 3.9 ± 0.2" W.C.
Readjust the gas pressure if necessary.
12. With the valve position at 100%, insert the combustion analyzer probe into the flue probe
opening and allow enough time for the combustion analyzer reading to stabilize.
13. Compare the oxygen readings on the combustion analyzer to the on-board O
value displayed in the Operating Menu of the C-More Control Panel. If the values differ by
more than ±0.5%, have your combustion analyzer calibration checked as soon as
possible. If the readings differ by more than ±1.5%, use the on-board O
calibrate the unit. Have your combustion analyzer serviced.
14. Compare the measured oxygen level to the oxygen range shown below. Also, ensure that
the nitrogen oxide (NOx) and carbon monoxide (CO) readings do not exceed the values
shown. If you are not in a "NOx-limited" area and/or do not have a NOx measurement in
your analyzer, set the oxygen (O
Combustion Calibration Readings – 100% valve Position
Valve Position
100%
Page 56 of 184
Benchmark 1500 - 2000 Boilers
CHAPTER 4 – INITIAL START-UP
) at 5.5% ± 0.5%.
2
Oxygen (O ) % Nitrogen Oxide (NOx)
2
5.0% - 6.0%
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913
Ph.: 800-526-0288
Carbon Monoxide (CO)
≤20 ppm
sensor
2
sensor to
2
<100 ppm
OMM-0097_0C
GF-142