Re: laser chilling

From: David Chambers (davidc@ccmi.salk.edu)
Date: Fri Jan 04 2002 - 14:06:44 EST


I doubt that San Diego coastal nights ever get cold enough to freeze a large-ish volume
of water such as you must have in your chiller.   I have a couple of thoughts however:
(1) build a cover over the chiller to keep the frost off. (2) Run the thing all night
without the refrigeration turned off if you anticipate a particularly hard frost (or
place a blower near the chiller and blow air on it, like they do in the orange groves).

You absolutely should not monitor your pipe diameter in FL2 unless you know exactly
what compensation to set for different degrees of frost.  You will soon find that the
chiller fills up with 10X Reagent B under these circumstances :-)

- David

On Thu, 3 Jan 2002 11:46:53 -0800
Andrew Beernink <ABeernink@novasite.com> wrote:

>
> Happy New Year!
>
> Is anybody using a ThermoNESLAB chiller to cool their lasers?  We have
> acquired an HX2000, which recommends the use of 30-50% glycol.  The big
> concern here in San Diego is those bitter-cold nights we suffer through all
> winter long!
>
> Seriously though, Coherent does NOT recommend using glycol, for they claim
> it will shorten tube life.  Unfortunately, NESLAB voids the warranty if its
> unit is run with straight distilled H2O because, in the event of East
> Coast-like freezing nights (I know, not likely!), the H2O's freezing and
> consequent expansion would cause a lot of damage to the chiller.
>
> Anybody have any experience or input here?  The chiller's flow rate is on
> FL1, the pipe diameter is on FL2...
>
>
> Andrew
>



This archive was generated by hypermail 2b29 : Wed Apr 03 2002 - 11:59:19 EST