Heraeus HS 9 Service Manual page 74

Service Instructions HERAsafe HS/12/18
B Field tests
B4 Cabinet leak test
8. Open the drain valve to pressurize the cabinet
with air to a reading of 500 Pa.
9. Observe the pressure gauge for 30 minutes to see
if the cabinet holds the pressure.
Acceptance according to NSF, 49, Annex F:
The cabinet must hold the pressure for 30 minutes;
the pressure drop must not exceed 10%.
Troubleshooting:
Pressure drop exceeds 10%: Spray leak detec-
tion foam or leak detection liquid onto all joints,
sealing, and connections of the cabinet, then re-
pressurize the cabinet with compressed air to lo-
cate leaks.
Leaks detected: Seal leaks with silicone.
Valid: 05.2001 / 50060091 / A
Reestablishment of the safety cabinet's operating
state:
1. Remove the apparatus.
2. Wipe off the leak detection foam or the leak de-
tection liquid.
3. Remove the plastic film or the sealing plate and
the sealing tape.
4. Secure the exhaust filter guard with the screws. If
applicable, reconnect the cabinet to the facility-
internal exhaust system.
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