CPSVG200 Digital Vacuum Gauge | NIST Calibration for Accuracy | Withstand 400 Psi Pressure, Easy-to-Read 5-Digit LCD | Perfect for Vacuum Testing in HVAC/R Systems

I am not an AC Tech by any means, however I have done my research and feel that this review will give someone some good info. When I first attached this device I could not pump down under 900 mic on any line set. I questioned the device at first, but then started looking for leaks, and as I read and read that if you cannot get below 500 mic then you have a leak somewhere. I started looking, first at the pump, found a small leak as I have a pump that has 3 connection ports that are capped with plastic caps. Then I found that I had not tightened a coupler enough and then found a bad flare (of course these items were all on different line sets). As soon as I took care of these small items all three line sets that I installed pumped down to below 250 mic. I also learned to read what the device was doing while the pump was running. It would bounce back and forth between numbers 830/840/850/840/830 etc and would go no lower. This told me that something was wrong. All the while I was watching the pressure gauge and it was holding at 30 psi. This device worked perfectly and I would recommend it to anyone who is installing any sort of HVAC system. I think my only gripe is that it turns off after 10 minutes so you have to turn it back on over and over.

Works perfectly vacuumed down my a/c system down to 200 microns.

Quality product, easy to use, beats the old thermistor vacuum gauge that was a standard in the trade for years!

I use this vacuum gauge as a reefer technician. It’s ease to use, simple and accurate. I’ve had other brands and pulled vacuums forever to try to get the gauge to 500 microns. Got this one and compared it against 3 other brands similar and found out that lots of time had been wasted trying to achieve my mark. So far the build quality has been great. The price of the part is little more expensive than others I’ve had in the past but you get what you pay for.

I got two of these. The first was very inaccurate above 1000 microns, the second was fairly accurate up to about 20 Torr. To be fair, most of the other micron gauges only go up to 10 or 12 Torr and I'm pretty sure this one uses a similar sensor. I guess the other models choose not to guess, and this one does guess. Still I prefer having some idea of the vacuum even when I know it is inaccurate.At first I though that both units that I got leaked pretty badly. I returned the first as it was inaccurate to boot. I usually use it to pull initial vacuum so the leak is not a dealbreaker. My process outgasses so the working pressure is much higher. A strange thing happened though. I left the chamber under vacuum for a couple of days (I thought to let a new gasket outgas) but low and behold the gauge stopped leaking as well. Either there is some outgassing going on, or a virtual leak to some other part of the gauge, but after the initial vacuum, I pulled the chamber down to 400microns and the gauge seemed fine ~5 micron per hour leakup on a 3 gal vacuum chamber.So If you have one of these sitting in a box thinking it leaks and is worthless, Hook it up to a vacuum chamber for a few days and see if it stops leakingOverall I am happy with the gauge for its wider range and lower price

Worked perfectly on a Mitsubishi mini-split install during line/system drawdown for leak detection.

I ordered one of these when I ordered a mini split unit. It "shipped" without ever giving tracking info. After a week Amazon gave a refund option (no tracking was ever provided). Ordered again at a higher price since it had gone up, and there was no option to reorder at the initial price.Received the replacement in a bubble package, that's normal. However, the inner plastic was missing chunks where the clamshell was previously opened (they were nowhere in the package), and everything was loose and rattling around. The battery was in the faux leather pouch and the gauge had oil residue on the fitting. Obviously used. I debated returning and ended up running a quick test which showed somewhat believable results.Mini split install lagged a bit, and when we tried to vacuum the system the gauge gave very inconsistent results. Cleaned with alcohol per the user manual, still couldn't get consistency nor accuracy. Ended up getting a different manufacturer's gauge and what do you know... the pump pulled vacuum down to <500 microns and held there.The CPS gauge is junk, maybe because I got a return, but I bet it was a broken return.*update*. I was able to chat with Amazon and explain the situation and have returned the gauge. Way to go Amazon!

The price is right on this vaccuum guage for the buyer, and the quality is high. It does have a plastic case so you still have to try to NOT drop it from very high...... might or might not break obviously. Even so, it is an excellent and simple device that will take merely a few minutes to install the new battery and have it ready to perform for you. I like the compact size, the very high quality of the MADE in USA parts and pieces, and the nice little protective carry case that comes with it. Compact, high quality, handy and easy to use, low priced..... how can you go wrong? It all fits in this small soft case that is about 6" long by 3" wide, by about 1.75" deep, that is so compact and well protected that it should provide long time good service. Do enjoy!UPDATE 29 May 2014: I finally received my new vacuum pump and put this to work. It takes a little bit for it to settle down at first, but after that, this is a fine instrument I could recommend to anyone. I like the compactness of it, and the quality in the brass fittings is excellent! (USA made, so no surprise there,eh?) It is easy to read, just large enough to be great. The ability to select any type of readout you desire, from Torr to Microns, is good too. It did not repsond well to upper vacuum levels of say 10" and less, but once pumped down below that, all worked very well and was stable. Enjoy!