Does this chiller suck that bad for my use?

Hey guys. Had a quick question about my chiller on my rotovap. I did do some
Digging on the math as far as cooling power and such, but it’s a little bit over my head in determining my issue, either this chiller is way under powered for my need, or I’m doing something wrong lol. I THINK this is the chiller that came with the rotovap. Anyway.
I have a polyscience mx08r-20-bv1b which matches a best value vacs sku. I think i found the right model so I’ll post some specs. I also have a 5l bvv rotovap.
The chiller fluid is nu-therm pf50
To start, the chiller takes 4 hours to get down to -20 from cool room temp. Not even doing cooling math, does that make sense?
Next, once it is at -20 I start running preheated crude which is about 110f and feed it into the roto which has a water bath temp of 103f. After recovering maybe 2-3 mason jars of material, the chiller is back up to +5-10 degrees and climbing. I have a mechanical cold trap at -50 which catches a lot that gets by the rotovap coil, but I’m sure I’m still losing some in the hose and to my pump.

This week I will be plumbing in a 50’ chilling coil to drop in dry ice to help the chiller. I can’t afford a new chiller or roto right now so I’m trying to do what I can to give it a boost…

I’m not saying this chiller sucks, just that it may be way underpowered for the rotovap they sold it with.

4 hours to get down in temp? And then only processing like 2-3 jars of etho crude before it’s too warm?

It is probably undersized for your usage, but I’d need more info, actually 5L is a pretty small roto so it could be a chiller issue if it used to work. If you’d like to DM me we can go through your system and resize it. This isn’t the first or second time I’ve seen this issue.

Alternatively since this is EtOH, we can discuss boost-chilling with LN2 as a stopgap.

Chiller not big enough. Just went through the same thing myself.
Used a bucket of ice and water with far far better results

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Hmmm. I’ve read people use just Ice water or running tap water. Cuz yea, this thing sucks lol. It’s crazy how many turn key setups were sold from open source and bvv type companies that were so under powered. I’m gonna try either the dry ice and 50’ coil, or maybe just your ice idea.

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that thing is worthless for rotovap use

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Oh. I’ve already realized this a long time ago haha. I’m surprised it’s the one that came with the roto. I was hoping someone would be like “You’re using the wrong fluid” lol. Gonna try ice water and see how cold I can get that down to

I’ve ran tap h20 for the past 2 yrs with good thuroughput.

Hoping my new leakphang chiller will do better.

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Hmmm. So I filled up a bucket with ice and water to test it. Seems it gets from between 0-5c. This temp should be sufficient to recover my etho? I can tell my roto recovers a lot more when it’s -20 as opposed to +5-10c… what’s really the safe temp zone to make sure I’m not losing etho to my pump? Will the ice bath at 0-5c work if I can keep that temp?

I recover at 10 c with well water


Looks like I’m going to buy some ice to Try it out. Cuz right now This thing gets through like a liter of crude and then takes 2 hours to get cold again.

I just want to make sure I’m not losing my etho by not being cold enough. Maybe that sounds dumb, I’m always learning. But seeing the etho slowly build in my mechanical cole trap lets me know a fair amount is getting by the coil.

I’ll let ya know how the ice goes. Sucks I gotta do some plumbing and shit now

Quick question… one of those things I overlook and may cause disaster. I have a 1/6 hp submersible pump that I usually use to push hot water through my closed loop for recovery. I was going to use this in the ice water and just plumb it into the roto. My question is, is there any chance that this pump tries to push too much water through and breaks the glass coil??



My rule of thumb is always buy the next size up chiller, 1 so it can keep up and if you want to up grade tour roto tou dont need to get a new chiller as well

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Depending on the size of your roto, i ran a 20l off of a simple wayer chiller with a cold trap. There pretty cheap and work good especially if your’s is smaller a 20L

this is the one i used for yrs,

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Ya should be just fine for ice water. Ran ice water through my lab society short path with a basic water pump and never had issues. The large bucket and coil Set up you go for the less strain you put on your chiller. And ice and water is cheap especially when it gets to temp. Grab a fat coil and throw it in a dumpster with ice water