Sheldon SHEL LAB SVAC1, Installation And Operation Manual, Page: 69 / 78

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MAINTENANCE
L
eak Rate?
Calculate and record the leak rate of the evacuated and isolated oven chamber:
1. Verify the oven chamber and shelving are at room temperature (20° – 25°C).
2. Verify the oven chamber is clean and dry to prevent outgassing from contaminants or water.
3. Close the chamber door, then open the vacuum valve.
4. Pump down the oven chamber to the lowest vacuum level your pump can achieve.
5. Write down the pressure displayed on the Vacuum Gauge as a positive number.
•
This is Record 1.
6. Isolate the chamber by closing the vacuum valve.
7. Allow the oven to sit sealed and undisturbed for 30 minutes.
8. Write down the pressure displayed on the Vacuum Gauge.
•
This is Record 2.
Leak Criteria
The oven chamber may be leaking if the chamber pressure rises by 0.1 or more during the 30-minute test
described above.
Vacuum Valve