Error message here!

Hide Error message here!

Forgot your password?

Error message here!

Error message here!

Lost your password? Please enter your email address. You will receive a link to create a new password.

Error message here!

Back to log-in

Sign in to set favorite

Refrigerant Recovery Pump Updates

Some excitement for closed loop extractors looking for an electric refrigeration recovery pump rated for R-600 refrigerant and more good stuff from Haskel! We are testing a electric new pump named the CMEP-OL that was designed specifically for our cannabis market, which is certified for use with flammable solvents, meets our process requirements, and has so far stood up to our field testing. We just moved it to the third production lab for continued field beta testing, with a thumbs up from the first two, a note that they are quieter than either the Appion or the TR-21, and faster than two TR-21's in both of their applications. We are currently running it in the field in as continuous service as possible, to rack up hours and tests its ability to stand up to our use and abuse, and so far, so good. We of course continue to recommend and rely on the pneumatic Haskel 59023 double stage and EXT420 single stage, which Haskel will now offer in a -2 configuration that is switchable from single to double stage using a single two way valve and two check valves. WolfWurx already converts both of the existing pumps to selectable single or double stage, using two three way valves, which is more complicated, though ostensibly with less back pressure without check valves. At least one other operator I know has converted his to selectable stages, using four two way valves. The Haskel's single drawback is its air consumption, but we have exciting news! The first, but old news, was that the Haskel performs most of our tasks single stage, so we almost double the output, and now the new news is that we've also determined that the Haskel never requires its full rated 100 psi pressure or 40 scfm air flow to meet our performance requirements at their recommended 60 strokes a minute. We don't have enough back pressure on a Mk VB installation to require more than 50 psi even running single stage, so we end up needing only about 25 scfm at 50 psi, or about a 6.25 hp (7 1/2 hp) screw compressor, rather than the 10 horse required for full pump capacity. The big difference that makes, is the selection of single stage screw compressors increases at 7 1/2 hp, and they use less electricity. For smaller installations, many of us have searched for an electric oil less refrigerant recovery pump that is rated for flammable refrigerants, and many use the non NEMA 7 rated electric Appion G-5, the ProMax-6000, the CPS-TR-21, and TRS-21, simply because they work. CPS delighted us recently with their offering of the TRS-21 sparkless, influenced by our markets needs, but not certified for use with R-290/600/600A. It currently appears to be struggling with infant mortality with the new pumps seals, and we await their solution. Here at the Pharm, we've also tested the R-290/600/600A rated CMEP loaned to us by Ecogreen, which performed well testing machines, but alas was not oil less, and are now testing a CMEP-OL, NEMA 7 oil less refrigerant recovery pump on loan from Here is a picture of four pumps, left to right, the Appion G-5, the CPS-TR-21, the CMEP-OL, and the CMEP. The Haskel that follows, is on WolfWurx, Inc Mk V waiting to be converted to selectable single or double stage, with a picture following of a unit converted using two three way valves. Zee Pumps-1-2zee pumps 001Haskel 59025-3 Haskel plumbed selective stage Haskel 59025-3 converted to selectable single or double stage using two three way valves. Haskel offers the EXT420 single stage and soon will offer their EXT420-2, which is selectable single or double stage, using one two way valve and two check valves, engineering test sled picture below: Haskel single-dual stage conversion

Haskel EXT-420-2 prototype test sledHaskel EXT420-2 prototype:

Wahoo, Wahoo!  Hee, hee, hee................


Lookacheer at whut Pharmgold is building a NEMA 7 Class 1 Div 1 6 cfm pump out of:

VaporHawg Pump innards

About The Author

Profile photo of skunkpharmresearch

This is the head cheese's account

Related posts


  1. Fuz

    I'm looking to purchase a knf double diaphram explosion proof recovery pumps for a precision extractor and was wondering if there was any testing by you guys here . Thanks

  2. petger

    How is the cmep ol testing coming along? Im looking to pick one up. Is a cold trap needed after the pump to cool down the gas before returning to the recovery tank?

      1. Dr heisenberg

        I have a cmep-ol that I've been running since July 2015. I run it a min Aug of 10 hours a day some days longer. I've had very few problems. Recently the fan blade came disconnected.......I think the cmep-ol is the pump for this industry. Another thing I'd like to point out is that I run a very custom extractor and the distance from the bottom of your base and the pump output line and the length of hose on your vacuum side make a difference. I have a tall base and long lines. I've been cycling through 15 pound runs with 32 to 36 pounds of solvent in 2.5-3 hours a run.....

  3. Nature Refined

    That after running their CM-OL for a few hours it has blown the piston seals and sent black material into their product. They also said they've gone thru 3 units and even had an engineer look at one and he determined that the pump was designed with the intentions that the solvent would be carrying lubrication through the pistons helping lubricate them. Now I know everyone has different experiences and I'm still gonna do my due diligence and run the CM-OL and see how much use I get out of it. I am very interested in your continued updates of your testing and I will also share my experiences. Thank you all very much and stay safe!

    1. skunkpharmresearch

      I saw the pictures posted, and it is hard to do an analysis from a distance, so am only offering observations and guesses until I do an analysis. The glazed cylinders and deposits look exactly like some of the pumps I've seen that ingested cannabis oil and had been run hot and dry. No oil less piston pump will tolerate that. We just moved our test unit to the fifth lab for trials without any complications, and before passing it on, I alcohol swabbed the intake and discharge ports between three and four, to see if it had been compromised. So far none of ours labs have done so. We will tear ours down when it does fail, and do both a personal failure analysis, as well as use a certified forensic lab to identify any accumulated substances. At that point I will be in a better point to comment.

      1. skunkpharmresearch

        PS: That does however bring up an excellent point! The CM EP OL is faster than dual TR-21's, which means the port velocities are higher and more likely to aspirate oil that is too close to the pump intake.

  4. Nature Refined

    First I just want to say thank you to every one of you that has put so much dedication and effort into our beloved industry. Information that you provide is one of the most valuable resources that we have and you continue to help in so many ways. I run an mk4c from terrp extractors and I had a CM-EP and stopped use immediately after my first recovery and realized it had been contaminated by the hemp seed oil in the CM-EP. I just finally received my long awaited CM-OL only to hear from a local industry leader

  5. skunkpharmresearch

    Morning Tim! An Apion G-5 works, but isn't rated for flammable refrigerants and Apion management has made it clear that they want no part of our market. We are still in the middle of seeing how long it takes us to break our CM EP OL test pump, so its longevity has yet to be determined, but the CM EP OL is the only electric oil less pump that I am aware of, rated for our purpose today. With such a huge market window, that will no doubt change with more off shore offerings, as well as domestic manufacturers looking for ways to tap into the demand. The only time proven oil less pump that I'm aware of this gorgeous morning, is still the Haskel pneumatic, but it is an even larger investment bite to swallow. Peace, GW

Join the conversation!