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LWR variables

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AEROSTATIC3:
Greets Beez...  after much reading on the attributes of the LWR and the HDR, and having a few LWR successes, SWIA's friend wonders about condensor length and/or diameter in relation to the efficiency of a LWR (or even a HDR).  In SWIA's prior dream I heard she used a 45cm long inner-coiled reflux condensor (approx. 12cm in diameter) on a 36 hr LWR; came out w/ beautiful gear. Now all her friend can obtain are some short fat Allihns, go figure. So I guess the question really is... Does size matter? (please no one with an inferiority complex lash out at me lol)--diameter, size, length, all of the above... Though she knows the little Allihns will perform efficiently, is it viable to throw 2 condensors together lengthways? Hell, or just opt for buying a real lengthy sumbitch?  Why or why not? SWIA's friend was told the longer AND wider the better, even for nanos or small reactions...

Amnesia:
A condensor is there to condense the vapours back into liquids, so as long as it keeps the vapours from escaping and condenses it back into the RXN it doesnt matter what the hell you use.

But of course a bigger one will do the job better, but overkill wont do anything of course.

Its just common sense.

AEROSTATIC3:
Thanks for the reply and time; yet you only offered that 'big' may be better, to wit: is or is'nt 'longer' necessarily better? SWIA's friend has witnessed 36+ hr refluxes w/ extra lengthy Allihns and watched the height of condensation SLOWLY rise during the 36 or so hour course of the reaction.  Was curious if that was a positive indicator of a more proficient reflux or not... or whatever. Any elaboration would be welcomed, Beez.

Amnesia:
Well it all depends on the surface area.
One that brings the most vapours into contact with the cool surface that is being cooled by the coolent will do the best job.

Whether that surface area is increased by an extra long condensor or whatever means you can think of then the condesation will be better.

Of course you could always decrease the temp of the coolent being used, which will increase the rate the vapours droping boiling the critical point and condense and drop back down.

So is longer better? yes because it gives the vapours more time to condense before they escape and more time to come into contact with the surface, but you should also be looking at the other factors.

geezmeister:
The LWR doesn't place a heavy demand on a condenser. IF you circulate cold or even cool water through it a 200 ml Liebig is enough of a condenser for cooks up to the two ounce range. Over that I usually use a 400 ml Liebig which is more than enough condenser for reactions up to four ounces. I can't recall ever needing to stack condensers, even with phos acid cooks.

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