- Hewlett-Packard Reference Manual

Preventive Maintenance

Flame photometric detector

198

6. Use compressed gas, air, or N

to blow out loose particles from the jet

and/or detector module body.

7. Inspect and clean deposits from the jet bore and from the threads

using a suitable wire. If the jet is damaged in any way, it should be

replaced. It is good practice to replace the jet rather than cleaning it,

particularly when extremely high sensitivity is required.

8. A new Kalrez O•ringseal (Part No. 0905•1103) must be used when

reinstalling the jet into the burner chamber.

9. Reassemble all parts of the detector module; reassemble the module

onto the instrument. A new Vespel ferrule (6.4 mm id, Part No.

0100•1061)should be used to seal the detector module to the transfer

line.

Caution

Be careful not to crush or side load the fused silica liner when

reinstalling the detector.

Whenever working with exposed fused silica tubing, wear eye

protection; fragments of fused silica could be released if the fused silica

is fractured or crushed.

WARNING

10. Reinstall the PMT assembly on the detector module; restore

instrument gases and power.

FPD leak testing (GC with electronic flow sensor)

If the system has an electronic flow sensor (EFS) with any FPD gas

plumbed through it (air, oxygen, hydrogen, or carrier), the system can be

checked easily and quickly. First, close all supply gases except for the one

plumbed through the EFS. Then cap off the detector exhaust tube with a

1/4•inchSwagelok plug (Part No. 0100•0196)and a 40% graphitized

Vespel ferrule (Part No. 0100•1061).

With the flow system deadheaded and one pressurizedgas plumbed

through the EFS, the flow reading should drop very close to zero. If not,