Complete Filtration Services Asov Auto Shut Off Valve, with Jaco Connectors

I purchased one of these as a replacement for a reverse osmosis water filtration system where the original auto-shut off valve started leaking. I needed a replacement quickly and no local stores had it, so I ordered with next day Prime delivery. There are others available, both from Amazon and on eBay that appear to be of better quality, but were not Prime. It arrived as scheduled, and while a slightly different configuration than the original shut off valve was fairly easy to install. That did require replacing a length of water line to make it longer as my original had all the ports on the bottom rather than the sides.I haven't really tested whether it shuts off when the tank is full. Basically I just replaced the old leaking valve with this one.It does seem quiet enough. Some of the higher priced auto-shut off valves advertise that they have less noise when water is flowing through the valve. I am very sensitive to noise and really didn't hear any noise through this valve, so that is fine.While the valve isn't made in the USA as other higher priced valves are, the quality seemed just fine, at least so far.As others have commented, the valve comes with no documentation at all. There are 4 ports on the valve, one marked IN, another marked OUT, and two more that are unmarked. There are diagrams available on the web, but basically connect it like this:IN: This port is the input port from the water supply after going through whatever pre-filters your system has. My system has an input particulate filter followed by 2 carbon filter stages prior to the RO filter.OUT: This is the output port from the valve. This should go to the input of the RO filterThe two remain ports may be switched without problem. One of the ports should go to the filtered output of the RO filter and the other to the storage tank and tap. This is just to essentially monitor the pressure at the output/tank so either direction is fine.The way the shut off valve works is there is a diaphragm that is pushed by the water pressure on the filtered water side. When that pressure is near the input pressure the diaphragm pushes a shut off valve to stop the water flow into the filter. This prevents wasting water and extends the life of the pre-filters by not having dirty water flow through them when the tank is full.The valve has been installed, and is presumably doing it's intended function. I really haven't checked the shut off function. It isn't leaking and causing a flood under my kitchen sink, so all is well. The Amazon Prime with next day delivery option for $4 is the best part of this valve. If you aren't in a hurry the $6 is hard to beat as well. There are more expensive options that claim to be better quality on both Amazon and eBay, but those would have taken a week or more for delivery. That made them not an option for me. If you need a replacement, and fast, buy this.

It was a perfect replacement for my old ASOV with the Jaco connectors. My old ASOV was about 15 years old and just recently started to run constantly making the water taste bad. After testing the old one by just blowing air into the inlet of the low pressure side and plugging the outlet of the low side, I could feel air coming out of the high pressure outlet, which proved that the diaphragm had a hole in it. The two water sources were mixing within the ASOV. About two weeks ago I replaced it with this new ASOV and it solved my problem and now the water tastes better. I just got my water bill today and it is $20 less than the previous month. It will be interesting to see next months water bill, hopefully less than this month. There are no instructions included with the ASOV, but it is easy to replace if you keep in mind that the thin half of the ASOV is the low pressure side and the Thick half is the high side.

As I expected

Great auto shut off valve! My old one didn't shut off water sometimes, maybe because the supply water pressure became too low. I tried 2 cheap chinese auto valves, but they didn't shut off water at all, even when I manually shut off my tank. This one works always, even at night when supply pressure decreases. Also it doesn't make any significant noise.

accurate description, fast shipment.

Perfect fix for RO system! I only needed the innards, but can't find them for cheap anywhere. I once saw the gaskets for reduce loud price on Watts Premier site. What's joke. Thanks so much for carrying this replacement for rock bottom prices!!!

It says on the description, nuts are included but mine did not.

I had it for a little while now - and it has been working great. My old valve stopped working - and this was the perfect replacement. The Jaco Connectors were a bit more effort to connect - but I have more confidence in their longevity.