Benchmark 5000-6000 Boiler Installation & Startup Manual
SECTION 4:
INITIAL START-UP
OMM-0123_E
• GF-207 • 12/17/2019 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page
52
of
95
NATURAL GAS
Combustion Calibration Instructions
8. Ensure that the leak detection ball valve downstream of the SSOV is open and the
manometer is attached and functioning properly.
9. Set
the
ON/OFF
switch
to
the
ON
position
.
10. Press the
MENU
key on the front panel of the C-More until
COMBUSTION CAL MENU
appears on the display.
11.
Press the Up ▲ arrow key until
SET
Stdby V Out (Standby Voltage)
setting appears.
Verify that it is set to
2.0 V
(the default). AERCO recommends it be kept at 2.0 volts to
prevent flue gas recirculation. Individually vented units in positive pressure boiler rooms
may set
SET
Stdby V Out
to
0
volts.
12. Press the Down
▼ arrow key until
SET Valve Position
appears, then press
CHANGE
.
13.
Use the Up ▲ arrow key to change the valve position to
50
%. The unit should begin its
start sequence and fire.
14. Next, verify that the manifold gas pressure, downstream of the SSOV, is within the range in
Table 4-1, for the model you are calibrating. 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 in the range specified in Table 4-1.
TABLE 4-1:
NATURAL GAS
Manifold Gas
Pressure Range @ 100% Fire Rate
Model
Single-Fuel
Dual-Fuel
5000
6.3” ± 0.2” W.C. (1.56 ± 0.05 kPa)
6.3” ± 0.2” W.C. (1.56 ± 0.05 kPa)
5000
Low Gas Pressure
2.6” ± 0.2” W.C. (0.65 ± 0.02 kPa)
6000
7.9
” ± 0.2” W.C. (1.97 ± 0.05 kPa)
7.9” ± 0.2” W.C. (1.97 ± 0.05 kPa)
6000
Low Gas Pressure
1.9” ± 0.2” W.C. (0.50 ± 0.05 kPa)
15. Once the manifold gas pressure is within the range in Table 4-1, record this value; it will be
used later, in Section 5.2:
Low Pressure Gas Test
, and Section 5.3:
High Pressure Gas
Test
.
16.
Press the Down▼ arrow key until SET Valve Position appears on the display, then press
CHANGE
.
17. Press the Up
▲ arrow key until the
SET Valve Position
reads
100%
, then press
ENTER
.
18. With the valve position at 100%, insert the combustion analyzer probe into the exhaust
manifold probe opening (see Figure 4-2) and allow enough time for the combustion
analyzer reading to stabilize.
19. Compare the
combustion analyzer’s oxygen readings to the O
2
Sensor value displayed in
the Operating menu on the C-More Controller. If the values differ by more than ±1.5% and
your combustion analyzer is correctly calibrated, the on-board O
2
sensor may be defective
and need to be replaced.
