4.3
Replacing the FID Quartz Jet
This section describes the procedure to replace the Quartz Jet inside the FID in the Maxum
II. The Quartz Jet is a thin quartz tube that includes the burner nozzle tip for the FID flame.
This item rarely needs replaced.
It will be necessary to power down the analyzer for this procedure. When performing this
procedure, it should NOT be necessary to remove the FID from the Maxum II.
4.3.1
Procedure to Replace Quartz Jet
1. Shut off the detector Hydrogen and allow the detector to cool down. Carrier gas should
remain on during cool down to prevent condensation.
2. Turn off all supply gasses.
WARNING
Possible ignition source. Failure to follow proper safety procedures may result in injury or
death.
If the analyzer is equipped with a purged methanator and explosive gasses are present,
it is necessary to wait at least 8 minutes for the methanator to cool after powering down
the analyzer before opening the analyzer door.
3. Power off the analyzer.
4. Remove Cap Screws (19) and detach Upper Detector Body (16) from Lower Detector Body
(3).
5. Unscrew the Burner Nut (10) and remove the Quartz Jet and attached hardware (7, 8, 9,
10, and 11).
6. Detach the Quartz Jet (11) from the Ferrules (7, 8, 9) and the Burner Nut (10). Make note
of the way they are assembled.
7. If Quartz Jet (11) is dirty or clogged, it may be possible to clean it using solvent in an
ultrasonic cleaner. However, replacement is recommended. If attempting to clean the
quartz jet, allow any excess solvent to evaporate before reinstalling.
8. Assemble the replacement (or cleaned) Quartz Jet (11) and associated hardware (7, 8, 9,
and 10).
9. Reinsert the Quartz Jet (and other hardware) into the Lower Detector Body (3). Before
tightening the Burner Nut (10), adjust the nozzle (flame tip). The distance from nozzle tip
to the Lower Body (3) should be 10.5 mm. Tighten the Burner Nut (10) with fingers. Then
retighten one quarter to one half rotation using a wrench. The nozzle can break if it is
tightened more.
10.Replace graphite seal (12) between the Upper Detector Body (16) and Lower Detector
Body (3) before reassembling the FID body.
11.Reattach Upper Body (16) and Lower Body (3) and reinstall Cap Screws (19). Tighten Cap
screws firmly but do not over tighten (about 1/2 turn past finger tight).
Flame Ionization Detector
4.3 Replacing the FID Quartz Jet
Maxum Edition II Detectors
36
Service Manual, May 2018, A5E42019847001