Hi, As far as the nitrogen stream delivery system is concerned - remove the leg(s) from the empty dewar and let it warm up to room temperature - make sure the dewar has not collected ice at the bottom. If it has, remove the ice and let the dewar dry - connect a high-vacuum turbo-pump to the leg valve, start the pump and once the pump runs quietly, open the valve and let the pump run for many hours while warming-up the lower end of the leg (hot-air gun but do not turn the heat on full power, warm is sufficient). Close valve and turn off the pump - place the leg(s) back into the dewar and fill it up
As for the AD51 unit - maintenance is due every 15000 hours (yours shows 26000 hours) - for sure you need to replace the carbon impregnated seals on the oil-free compressor pump heads* (not rocket science) - replace the compressor delivery filter too - check that all air and purge valves are working *Quote from the maintenance manual, page 6: The eventual failure of the cup seal is a very sudden process and the dryness of the dry air will deteriorate rapidly, also the maximum flowrate of dry air will drop below 25 litres/minute (perhaps less than 10 litres/minute). Good luck, J. -- Dr. math. et dis. nat. Jeroen R. Mesters https://orcid.org/0000-0001-8532-6699 University of Lübeck Institute of Biochemistry https://www.biochem.uni-luebeck.de phone: +49-451-3101-3105 Ratzeburger Allee 160 23562 Lübeck Germany -- > Am 09.02.2023 um 09:14 schrieb Natesh Ramanathan <nat...@iisertvm.ac.in>: > > After they saw via video call that the Dry Air Unit was not maintaining more > than 15 L/min Air flow, even after adjusting the flow rate knob.. they gave > a quote for service... As always, the cost of the service engineer visit > and spares were prohibitively expensive and... ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
