RBGKEW1490 Maintenance and repair of LNI Swiss Gas nitrogen generators

In the Jodrell Laboratory, two LNI Swiss Gas nitrogen generators supply high volumes of high purity nitrogen to four liquid chromatography-mass spectrometry (LCMS) systems (total value exceeding £1m). The LCMS systems are heavily used in the delivery of externally-funded projects and Kew's commercial work. Without nitrogen, the LCMS systems cannot be used. Thus, ensuring the nitrogen generators are properly maintained is critical. LNI Swiss Gas nitrogen generators employ patented scroll pump compressor technology and it is this technology that results in them being inaudible above the typical noise level in an LCMS laboratory. At the time of purchase, the tender process revealed they were unmatched in their quietness with noise level being an important specification in the tender (for H&S reasons). The generators also produce a purity of nitrogen gas that, at the time of procurement, exceeded that of other noisier generators tendered. The annual contract sought covers two preventative maintenance visits for each generator including parts scheduled to be replaced at the service interval, 25% discount on repair labour and 72h response time. Both generators are due for an overhaul of the scroll pump in 2026 resulting in an increased service contract cost in 2026 to cover the extra parts required.