Kozyvacu Dual-Stage Rotary Vane Vacuum Pump for HVAC/Auto AC Refrigerant Recharging, EPoxy Resin or Wine Degassing, Laboratory, Medical or Milking (500P)

I had no issues with the pump. It sucked my honda civic system down to-30 very quickly. Ran pump for almost 1 hour straight with no overheating or cutting out. I will say it was 50 degrees outside when I used it. Pump makes some strange sounds when running however it did a great job. After 10 minutes or so the pump was not putting out any mist. The way I understand the manual once mist stops them moisture should be out of the system. The oil that's included was a little more than needed to fill the pump so I have extra if ever needed. Good pump for the occasional users.

I use this for degassing silicone and epoxy when casting or molding objects. Works great. I use a pair of vacuum chambers, a 3 gallon and a 10 gallon, either individually or hooked up at the same time. Getting vacuum hoses is actually pretty tough - there's very little documentation about what types of fitting are the right ones for vacuum use, which ones are compatible with which others, which ones have nice quality of life features like swiveling, and which ones leak unless used with sealing grease. That's not the pump's fault though.

Re Kozyvacu 5CFM 2-Stage Rotary Vane Vacuum Pump I've used this pump a few times to pull a vacuum for cars A/C. I found it to be efficient and surprisingly quiet. It pulled the maximum vacuum within a matter of minutes. I have left it on for about 1/2 hr with no problems (it obviously got a little hot as expected). Build quality seems fine. Other folks have mentioned the oil mist from the exhaust. I can't comment on if this is normal for vacuum pumps but knowing it may do this I connected a length of pipe to direct the exhaust. This issue wasn't a problem to me. (Note, I chose the 2-stage, 5 cfm model)

This vacuum pump is well built and heavier than I expected. Exceptional quality build. I used it to vacuum my auto AC and it went to about 27 mg in less than 2 minutes. If left for a half and hour it goes down to about 29.5 mg, provided you don't have any air leaks. Its very sturdy and performs exceptionally well. Less noisy than I expected.

I bought this as a backup vacuum pump for my Harvest Right freeze dryer. The pump failed and I replace it with another Harvest Right pump. That pump failed after two runs and was returned. So, I put the Kozyvacu pump into service. It's worked like a champ ever since. I did have to run to Napa to get fittings to make it work with Harvest Right. The new fittings required removing the check valve which means you need to operator the Harvest Right the way you would if the HR vacuum pumps check valve fails (which is a very common occurrence). Pros: 1) Price 2) It works. It gets a small HR to 500mTorr in 4 minutes and a medium HR to 500mTorr in 8.5 minutes. 3) It's much lighter than either the JB or HR vacuum pump. Cons: 1) No check valve 2) Draining the oil for filtering is messier than with either the JB or HR pump. 3) It vents oil vapor on startup. Less than my JB ever did, but more than an HR pump 4) You must buy additional fittings (Napa has them for $12) 5) Works on both my small and medium HR freeze dryers. I don't know how long lived it will be but I'm about 6 months into owning a HR (a small from HR and a medium that was a derelict I found on Craigslist) and I’ve gone through 2 vacuum pumps. The JB with the Craigslist machine was a basket case to begin with, the new HR is still functioning but a backup HR I bought failed after 2 uses. I’m happy with how the Kozyvacu pump works, but it’s not perfect and requires a small amount of disassembly to add the correct fittings. But otherwise it’s a great value and seems robust so far.