Propane Gas Combustion Calibration - Watts Aerco Benchmark OMM-0124 Installation And Start-Up Manual

Benchmark 5000-6000 Boiler Installation & Startup Manual
SECTION 4: INITIAL START-UP

4.5.2 PROPANE GAS COMBUSTION CALIBRATION

These instructions apply only to units running PROPANE gas. Instructions for doing combustion
calibration on a unit running Natural Gas appear in the previous section, 4.5.1.
PROPANE Combustion Calibration Instructions
1. Open the water supply and return valves to the unit and ensure that the system pumps are
running.
2. Open the PROPANE
3. Set the C-More Controller's ON/OFF switch to the OFF position.
4. Turn external AC power to the unit ON. The display will show a description of the unit and
then the time and date.
5. Press the MENU key on the front panel of the C-More and access the Setup menu, enter
the password 6817 and then press the ENTER key.
6. 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 % and the MANUAL
LED will light.
7. Adjust the air/fuel valve position to 0% by pressing the ▼ arrow key and then press
ENTER.
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 gas pressure downstream of the SSOV is within the range in Table 4-4
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
approximately shown in Table 4-4.
TABLE 4-4: PROPANE Gas Pressure Range
Model
2.0" ± 0.2" W.C. (0.50 to 0.05 kPa)
5000
4.2" ± 0.2" W.C. (1.05 to 0.05 kPa)
6000
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.
OMM-0123_E • GF-207 • 12/17/2019
supply valve to the unit and then slowly open the Pilot gas valve.
Single-Fuel
Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST
@ 100% Fire Rate
Dual-Fuel
2.0" ± 0.2" W.C. (0.50 to 0.05 kPa)
4.2" ± 0.2" W.C. (1.05 to 0.05 kPa)
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