Purge Coil And Filter; Replacing The Fid Mesh Filter - Siemens Maxum II Service Manual

4.1.4

Purge Coil and Filter

Older analyzers had coils of stainless-steel tubing to provide an exhaust path for purged
spaces. In newer analyzers this has been replaced by a metal filter or eliminated altogether.
The two devices are shown in the photo below.
Figure 4-1
4.2

Replacing the FID Mesh Filter

This section describes the procedure to replace the mesh filter inside the FID in the Maxum
II. The mesh filter is a small round filter located inside the combustion chamber of the FID.
This filter is for the combustion air input. Because of the very small diameter of the air restrictor
though which combustion air passes, it is unlikely that the filter will become clogged.
Because it is difficult to remove this filter without damaging it, in the event that the filter does
become clogged or it should become necessary to remove the filter for some reason, then it
should be replaced and not reused.
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.
The following figures are intended for use as a reference throughout the procedure. The
numbers in the diagrams relating to individual components are referenced in parentheses in
the procedure steps.
5
Figure 4-2
Maxum Edition II Detectors
Service Manual, May 2018, A5E42019847001
Purge Coil compared with Metal Filter
6
4
3. Detector Body (Bottom)
4. Filter
5. Retainer Clip - Small
6. Retainer Clip - Large
3
FID Mesh Filter and Retaining Clips
Flame Ionization Detector
4.2 Replacing the FID Mesh Filter
33