Preventive Maintenance
Flame photometric detector
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this indicates a leak in the system. Begin checking possible leak sources
and monitor the EFS to determine when the leak has been eliminated.
Possible leak sources, in order of probability are:
1. septum
2. column fittings
3. supply line swage•typeplumbing connections
4. detector block O•ringor Vespel seals
5. other system plumbing
Caution
When leak•testingthe flow system under pressure, do not exceed
210 kPa (30 psig), because higher pressures may damage the detector
block window or seals.
FPD leak testing (GC without electronic flow sensor)
If a leak is suspected in an instrument without an electronic flow sensor,
possible leak sources can be checked in the order listed (1 through 5)
above. This can be done by capping off the detector exhaust and
pressurizing the system to 140 kPa (20 psig). Then close off the supply
flow and monitor the rate of pressure drop. Pressure should drop no
more than 7 kPa (1 psig) per minute.
If using liquid solution to locate leaks, to avoid a potential shock
hazard, place the main power switch in its off position and disconnect
the main power cord. Be careful not to spill leak solution on electrical
leads•especially the detector heater leads!
WARNING
Note: Except when leak testing, it is best to leave the detector module at
operating temperature at all times (whether the flame is lit or
extinguished) to minimize thermal expansion/contraction.
