Is a chiller necessary for a 2L Rotovap?

If I am running a water aspirator would i even need to get a chiller?

How are u going to condense your vapors?
Even an aquarium pump with ice water counts as a chiller.


Probably more so than a bell on a bicycle :wink:

You heat the solvent to evaporate it. You must then cool it to condense it again.

If you’re flowing water down the drain from your aspirator, flowing that water through your condenser before it goes down the drain will certainly allow you to use the rotovap. Probaly not at max speed.

If you’re using a recirculating aspirator, you can certainly throw ice packs in it and get double duty in a pinch


Okay what is the best way to keep the water chilled in the aspirator? Could this be done by dry ice/icecubes?

So yes on the recirculating aspirator.

Ice packs. You can swap them out. Whereas ice makes things overflow.

You’d be better off with a vac pump and a chiller imo.


Ice packs, lots and lots of ice packs if u use ice ur gonna need to drain the water and thats gonna be a pain. I used to use 30 ice packs in rotation.
Yup, what cyclo said :call_me_hand:a chiller is so useful.
U can make a chiller yourself for cheap just modify a AC consender coils so they are in a liquid bath then circulate with an aquarium pump


I think I left a link to making a vac pump out of a refrigeration compressor around here somewhere.

So with two AC units you could make both a vac pump & a chiller.

You played either of those games @Roguelab?


when you say 30 ice packs, are you talking in one batch? and what size roto vap were you using?

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5L roto, i used a SS stainless coil inside a 5 gallon gatorade insulated bucket. I started the day with 2 bags of ice from a local grocery store and would rotate 6 ice packs every half-full hour too keep the water cooled
Lol that would be a big vessel if u put 30 ice packs at once.
I got maybe 1-1.5L/hour using the icepacks. Now with an oversized condenser i can hit 3-4L/hour no problem. Fastest ive gotten it is 5L/hr


Not all at once…


If i were to go vac and chiller would i also need to add a cold trap?

That depends on your choice of pump and chiller.

Using a diaphragm pump that can injest solvent without issue is one alternative.

Keeping your operating parameters within the capability of your chiller (eg bigger chiller, less heat, or less vac) is another way to operate without a cold trap.


Always have a cold trap if u can, even one just filled up with no dry ice in it will help alittle.
I use a simple vacuum pump for hvac ($150 new) and use to use a needle valve to keep the vac consistent. Now i use a vacuum controller ($300 off ebay)


if you need the lower temp, i suggest that you could use chiller.

Yes the vac pump is easy good video s and tutorials on the the all knowing :grinning:
The window AC also is not to hard
Working on a split unit now summer is comming want to keep all heat producers outside

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cheesus kryst… thanks man! i was breaking my head on how to replace the chiller!!! any other advice on mantaining temp on the head???