Cmep vs trs

Alright boys, I am a super dumbass and want to know what pump I should be using. Right now I am using a trs pump and running it 8 hours a day. Recovery seems slow and it seems to get really hot. Would I gain speed if I upgrade?

No pump is the best pump


CEMP sucks & needs rebuilds constantly unless you know exactly where to keep your pressures.

Go passive, Hot & Cold for the win


If you are running one trs pump and it’s taking you 8 hours, I would say throwing the cmep in there would shorten your day to about 6 hours.


Just to clarify i run 8 hours a day, but thats multiple runs per day.

The problem I am having is I live in a tiny ass town, and I live 15 min from that. Less than 1000 people in my city, and 0 dry ice. I have to drive an hour and a half to get it. So im trying to make due with what I have

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TRS 21 pumps are lil beasts the maintenance is very easy and straight forward. If you wana try something throw a second TRS 21 at it. (If you do add a second pump its important that you also purchase some JIC tee fittings) Its important that you do not daisy chain the pumps. If your running both at the same time both pumps should be pulling and pushing to a single point. (This is where the Tee comes in to play.)

I.E. both (ins) need to be pulling from your desiccant (Mol Sieve) and Both (outs) need to be pushing into the condenser coil.

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If you go with a cmep you can add a water/chiller cooled radiator to it and it will help with cooling. Ive ran 4 cmep off just ice water they run alot cooler and if ran properly they will last in my experience and the way i run them. Trs21’s arw good if you have high psi in your recovery tank but take alot more to cool the out going gas since they run so hot.


It cost twice as much in dry ice to do half of what the cmep would recover in the same time.
Example. Cmep uses 50lbs of dry ice to recover 50lbs when the trs uses 100lbs to recover 50lbs of solvent. Trs 21s run hot so you waste more ice. Cmeps are also faster

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So im new to this forum as far as signing up for an account but I’ve been snooping around for a long time. You guys are amazing, thank you so much


You could recover passively with that much dry ice…

I am doing 70lbs of butane with 100lbs of dry ice (and I’m using the same 100lbs for chilling during injection)




Oh man if that works like it shows that’s gonna save my lab a shitload of money.

Isn’t this pretty inefficient? Also if anyone actually goes and reads the history of dry ice. This was one of the first methods discovered.

So kind of funny your feeding a history lesson here :+1:t3:

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Thats like the worse way to make dry ice. It wont be cheap

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CMEP is better than Trs-21 hhands down.
Mine doesn’t suck and i haven’t had to rebuild it. i took it apart after 3 months and the heads were clean and dry.
you need to take care of her and she will treat you right.


No doubt ran the first 4 i had for almost 2yrs 8-10 hrs a day before one went out and i just rebuilt all of them any way. Keep them elevated so gas doesn’t pool in them and dont run them into vacuum very deep or not at all and tbey will last. Plus there cheap and easy to fix

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The OP mentioned he was not able to get dry ice due to being in a remote area so Inefficient is better than an hour Or more drive to get dry ice on a hot day

When your in a remote area Ya gotta make do with what ya can get & co2 is dirt cheap

Edit: just make sure your tank has a dip tube

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just use the lco2 as the cooling medium, making ice with it wastes like 75% of the co2.

Wouldn’t one have to circulate the lco2 somehow ? & if so how would one do that on the cheap?