Advertisement
Benchmark 750-3000 Boiler Installation & Startup Manual
SECTION 5 – SAFETY DEVICE TESTING
LOW Gas Pressure Test Instructions: BMK 3000 ONLY
7. Press the MENU key on the front panel of the C-More Controller and access the Setup
menu, enter the password 6817 and then press the ENTER key.
8. Place the unit in MANUAL mode and adjust the Air/Fuel Valve position (% open) to 100%.
9. While the unit is firing, read the CO value on the combustion analyzer and slowly decrease
the incoming gas supply pressure until the CO reading is approximately 300 ppm.
10. Take a reading of the inlet gas pressure. If the inlet pressure is below the minimum
calculated in step 4, above, then increase the pressure to match the calculated minimum.
11. Slowly turn the indicator dial on the Low Gas Pressure switch until the unit shuts down due
to a gas pressure fault.
12. Readjust the inlet gas pressure to what it was prior to the test.
13. Press the CLEAR button on the C-More Controller to clear the fault.
14. The fault message should clear and the FAULT indicator should go off. The unit should
now restart.
MANUAL SHUT-
OFF VALVE
LOW Gas
Pressure Port
Install manometer here for
Low Gas Pressure test
Figure 5-2: BMK 3000 LOW Gas Pressure Test Components
OMM-0121_D • GF-205 • 5/9/2019
SSOV
TO
AIR/FUEL
VALVE
HIGH GAS
PRESSURE
SWITCH
Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST
NATURAL
GAS INLET
LOW GAS
PRESSURE
SWITCH
LOW GAS
BALL VALVE
Alternative
LOW Gas
Pressure Port
Page 81 of 122
Advertisement
