FTS Chiller
Karen Ann Smith (karenann@unm.edu)
Tue, 21 Aug 2001 12:51:55 -0600
I have a FTS XR1185 chiller. I am using it to keep a peptide at around
6C so I don't need it to go too low, but I do need it to stay cold for a
long time.
I have been using house nitrogen (liquid N2 boiloff) after my dried air
froze up the chiller a couple of week ago. Now I purge the lines for a
good 10 minutes before starting the chiller.
I can get the temperature at the chiller down to -66 or so. It stays
there for at least 6 hours (probably 12-18) and then starts to warm up.
This morning when I came in, the chiller was at -45 and the sample at
about +15.
There did not seem to be any blockage of the air flow. I was running at
about 535liter/hour which is quite a bit less than the 1680 liter/hour
(1scf/m) that the system is rated for.
The room temperature was at a reasonable 72F this morning, so room
temperature was probably not a factor.
So- should I try running at 1600 liters/hour? Won't that bounce the
sample around?
Is there some other trick, or should I just revert to liquid nitrogen
boiloff? (How long does a Bruker 25L dewar last, anyway?)
thanks,
kas
--
Karen Ann Smith karenann@unm.edu
Director, NMR Facility Adj. Asst. Prof.
Dept. of Chemistry Clark Hall
University of New Mexico Albuquerque, NM 87131
505.277.4031 url: http://www.unm.edu/~karenann
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