Benchmark 750-3000 Installation & Startup Manual
SECTION 5
– SAFETY DEVICE TESTING
OMM-115_D
•
GF-200
•
5/9/2019
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126
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.
Figure 5-2:
BMK 3000
LOW and HIGH Gas Pressure Test Components
TO
AIR/FUEL
VALVE
MANUAL SHUT-
OFF VALVE
SSOV
LOW Gas
Pressure Port
Install manometer here for
Low Gas Pressure test
LOW GAS
PRESSURE
SWITCH
HIGH GAS
PRESSURE
SWITCH
Alternative
LOW Gas
Pressure Port
LOW GAS
BALL VALVE
NATURAL
GAS INLET
(P/N 22171 shown)
