Inspection and Maintenance Instructions for 7FA.05 Gas Onl
and Dual Fuel Gas Turbine
GEK 116862
The empty and full weights of all cylinders are permanently stamped on the cylinder valve bodies.
Each time the cylinders are weighed, the date and net weight should be recorded on the attached tag.
E. CO
2
High Pressure System Tests (Clean Agent Systems)
Two separate tests are necessary to ensure that the high pressure CO
2
system is ready for operation.
These tests are: (1) Solenoid Pilot Valve test and (2) “Puff” test. Description of the test procedure can
be found under the Fire Protection section of the Service Manual.
F. Low-Pressure CO
2
System Electric Release and “Puff” Tests (where applicable)
This system consists of a single pressure vessel, refrigeration system, gauges, alarm system and
safety vent assembly, all enclosed within a steel housing on a single, all-welded base. The
refrigeration system automatically maintains the CO
2
in the pressure vessel at approximately 0°F (–
17.7C) and a vapor pressure of 300 psi (20.6 bars).
Operation of the low-pressure CO
2
system is fully automatic. Once installation is complete, the sys-
tem requires only periodic inspection and maintenance (except when fire protection service, or
system malfunction necessitates major servicing and checkout).
Two separate tests are necessary to ensure that the low-pressure CO
2
system is ready for operation.
These are (1) the electric release test and (2) the “puff” test.
Electric Release Test
Check the wiring in the circuit by short-circuiting each fire detector in turn. Each time this is
done, solenoid valve 20FP should energize. Before performing the Electric Release test, the
system must be disabled by means of the isolation valve in the control cabinet.
“Puff” Test
The “puff” test consists of discharging a small amount of CO
2
into the system as a final check on
the operation of the release mechanism and to be sure that all pressure-operated latches and
ventilation dampers operate properly. Conduct the test as follows:
1. Inspect the ventilation dampers in the accessory and turbine compartments and latch them in
the open position with the CO
2
-operated latches.
2. Check to see that solenoid valve 20FP is de-energized.
3. Clear all personnel out of the accessory and turbine compartments. Make sure all ventilating
fans are on during and after testing to remove the discharged CO
2
from the area.
4. Cycle each pneumatic timer by operating a push button station or by operating the manual
release to determine that the timing is as required. Cycling should be done with the
discharge manifold under pressure, but with the tank shutoff valve closed so as to provide
only a “puff” discharge vapor.
5. Cycling of the timers will also serve to prove operation of the pressure switches and in turn
the performance of electrical shutdown and annunciation.
NOTE
The timing cycle can be aborted by closing the isolation valve and resetting the
pressure switch after the timer re-sets.
© General Electric Company, 2011. GE Proprietary Information. All Rights Reserved.
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