- Loud, throaty noise coming from the scroll pump
- Vacuum is fine
- Edwards XDS 35i
- Edwards XDS 46i
- Edwards XDS 100B
Loose tip dust
FIX or WORKAROUND
- Ballast the scroll pump by turning the knob from 0 to II.
- Leave for 20–30 minutes.
- Return the knob back to the 0 position.
For instructions on ballasting the pump, see Article 7466 - How do you ballast the Edwards scroll pumps?
Ballast once a week on Monday mornings.
When running in APCI mode or with high LC flow rates (~1mL/min), put the dial in the I position.