Heraeus HS 9 Service Manual page 80

Service Instructions HERAsafe HS/12/18
B Field tests
B7 Airflow pattern test
C. Work opening edge retention test:
1. Test method, Fig. B7: Outside the front side of
the cabinet, pass a smoke tube from one end of
the work opening to the other at a distance of 4
cm (1.5 in), pay particular attention to the edges
and corners of the work opening.
2. Acceptance according to NSF, Annex A: No
smoke escapes through the work opening, or is
drawn to the work surface or billows over the work
area.
D. Front window and upper edge seal test:
1. Test method, Fig. B8: From inside, pass a
smoke tube along the window frame seals and
along the upper edge of the front window.
2. Acceptance according to NSF, Annex A: No up-
ward refluxing, nor escape of smoke from the
safety cabinet.
.
Troubleshooting:
Refluxing and dead spots in the airflow:
Check the set point of inflow and downflow air.
Replace the window.
Valid: 05.2001 / 50060091 / A
Figure B7 / B8
Fig. B7, Work opening edge retention test
Fig. B8, Front window and upper edge seal test
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