AERCO BMK 6000 Dual Fuel - Manual (Page 82)

Benchmark 6000 DF Installation, Operation & Maintenance Manual
CHAPTER 6 – SAFETY DEVICE TESTING
Page 82 of 219 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 OMM-0096_0B
03/21/2014
Ph.: 800-526-0288
GF-141
Low Gas Pressure Fault Test – Continued
5. Remove the cover from the Low Gas Pressure Switch and set the dial indicator to 2 (the
minimum).
6. Open the external gas supply ball valve upstream of the unit.
7. Place the unit in Manual Mode and adjust the Air/Fuel Valve position (% open) to 100%.
8. While the unit is firing, slowly decrease the incoming gas supply pressure while reading the
CO value on the combustion analyzer until the CO reading is approximately 300 ppm.
9. 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.
10. Slowly turn the indicator dial on the Low Gas Pressure Switch until the unit shuts down due
to a gas pressure fault.
11. Readjust the inlet gas pressure to what it was prior to the test.
12. Press the CLEAR button on the Control Panel to clear the fault.
13. The fault message should clear and the FAULT indicator should go off. The unit should
now restart.
14. Repeat the previous procedure on the PROPANE gas train, starting with the 1/4“ plug next
to the PROPANE Low Gas Pressure switch, shown in the bottom-half of Figure 6-1A.
Figure 6-1A: Low Gas Pressure Switch Locations & Test Point Locations
PROPANE LOW GAS PRESSURE SWITCH
(5.8” W.C.)
NATURAL GAS
LOW GAS
PRESSURE SWITCH
(8.5” W.C.)
NATURAL GAS
TEE with 1/4" PLUG (Install
manometer here for LOW
GAS PRESSURE test)
GAS
INLETS
MANUAL
SHUT-OFF
VALVE
TO AIR/FUEL
VALVE
PROPANE
TEE with 1/4" PLUG
(Install manometer
here for LOW GAS
PRESSURE test)