The outcome was that all 3 machines that had new seals replaced on the first day achieved an ultimate vacuum of 9 mbar. Contacts: Ian Nichols Organisation: University of Bristol Department: School of Chemistry Country: United Kingdom Product: Hei-VAP and Vacuum Seals Case Study No: CS1095 The SituationHeidolph rotary evaporators (Laborota 4000 model) are used in the undergraduate teaching laboratories at the University of Bristol. The teaching laboratory staff contacted Radleys as they suspected that the machines will need new vacuum seals soon. The vacuum seals had never been replaced on the machines, which have been installed for over 10 years. A vacuum of 25 mbar could still be reached on the majority of the 21 machines. The ObjectiveAssess the condition of the existing seals on the teaching labs’ rotary evaporators, replace any that need immediate replacement and keep a stock of spares for future maintenance work or emergency repair. We assessed the performance of the vacuum pumps used with the rotary evaporators, so measured the pump final vacuum with and without a rotary evaporator attached, in order to identify which of the two might need attention. The ResultsRadleys supplied replacement vacuum seals and showed the teaching laboratory technicians how to replace them. All 3 machines that had new seals replaced on the first day achieved an ultimate vacuum of 9 mbar. The staff from Radleys were very helpful and thorough in their instruction on the replacement process and in supplying background documentation for reference.Ian Nichols, University of Bristol