Maintenance
Maintenance applies mainly to the filter element.
Check the filter regularly and replace it, if neces-
sary.
The service life of a filter depends mainly on how
polluted the air is. Check the filter in intervals that
are short enough such that you can anticipate any
defects or problems before they actually occur.
Replace the filter immediately if any of the following
is true:
The defined final differential pressure has been
reached.
Hygiene problems (micro-organisms, fungal
spores, odours, etc.)
Filter defects (particle count has been
exceeded)
The maximum filter usage time has been
reached (8 years, to VDI 3803, part 4).
You may replace a filter even before the defined
final differential pressure has been reached if it is
more economic.
Removing the diffuser face
Some maintenance jobs, such as sealing integrity
testing, leakage testing, filter changes or cleaning,
require you to remove the diffuser face.
Fig. 7: Removing the diffuser face
Unscrew the knurled screws (Fig. 7/2) and
remove diffuser face (Fig. 7/1).
Leakage test on an installed filter
A functional test of the filter system is required to
ensure that there are no leaks and that the filter ele-
ment is without any defects (no small holes on the
filter frame or on the seal, no leaks at the filter
frame).
1.
Remove the diffuser face,
Ä
‘Removing the
diffuser face’ on page 9
.
Fig. 8: Measuring tube
①
Measuring tube
∅
8
×
1.5 mm
2.
Open the measuring tube by removing the
cheese head screw.
3.
Measure the particle concentration on the
upstream side to ISO 14644-3 B6.
4.
Measure the particle concentration on the
downstream side to ISO 14644-3 B6.
If there is a leak, seal it; then test for leak-
ages again.
5.
Close the measuring tube by inserting the
cheese head screw.
6.
Re-install the diffuser face.
Maintenance
TFM Particulate filter modules for ceilings
9