APEC Water Systems Auto Shut Off Valve Replacement Part (ASO)

My RO system started running constantly after a few years and I noticed an increase in my water bill. This part installed in 5 minutes and fixed the problem.

There are many choices for this item. This one works much better than the previous replacement. Good flow, good tank refill control, looks solid and not cheaply made.

Great product. It fixed the trickling problem I was having with my existing RO system. My existing system is a Watts RO water filter system. My two-year-old Watts RO unit never stopped trickling water into my sink drain. It just kept running and running and the sound was annoying, not to mention that it was wasting water. So I first changed the filters (not the membrane), but that didn't fix the issue. So I decided to change the auto shut off valve before spending a lot more money on the RO membrane. Lucky for me, the shut off valve fixed the issue. The water now stops trickling only a couple minutes after I fill a glass. However....this valve didn't fix my capacity issue. When my RO unit was new I could fill a 1.5 liter bottle in one shot, then it got to the point where I could barely fill an 8oz glass before the water ran out. I fixed the capacity issue by adding a little air pressure to my RO tank using a bike pump.

I can confirm this ASO valve is a suitable replacement for 1/4" tubing ASO valve used in the Watts 4 stage RO filtration system. After installing the replacement I learned some tips for those who wanted to save a little money by using a "non-standard" or "off brand" replacement part for ANY RO system.1. Ensure correct tubing size. Make sure you know the correct tubing size for the feed lines in your RO system. This product is compatible with 1/4" tubing only.2. Install ASO Valve correctly. If you, like me, are installing this ASO valve as a replacement in a NON APEC RO system, the color coding with the ports may not match. The blue collet on the "in" side of the ASO valve connects to your COLD WATER SUPPLY. The white port connects to your RO Tank. From there it's simple to connect the "out" side keeping the tube color pattern consistent.3. Check ASO Valve function. After you have turned the water supply back on, you will probably hear the system functioning and also that draining sound which may have started you down this path to begin with. TAKE HEART! Here's what you do: SHUT OFF THE TANK VALVE AND WAIT 5-10 MINS! If the ASO valve is installed correctly and there are no other problems with your system, the ASO valve should engage once the correct pressure is reached in the system and the water will stop draining.REMEMBER, THE SYSTEM WILL NEED TO PRESSURIZE BEFORE THE ASO VALVE WILL FUNCTION! THIS CAN TAKE 5-10 MINUTES.IF, AFTER 5-10 MINS, THE WATER CONTINUES TO DRAIN, THE VALVE MAY BE FAULTY OR THERE IS ANOTHER REASON YOUR RO SYSTEM IS NOT REACHING ADEQUATE PRESSURE!The main take away is, once you install the ASO valve, the system will need to re-pressurize before it will stop draining and that can take 5-10 mins. Do not expect the water to stop draining immediately. Also, if your RO tank has inadequate pressure it may need to be re-pressurized. When the tank is full of water, it should read at least 40 psi.Hope this helps!

Fits my old Watts Premier RO Pure 4 stage system. I moved one tube at a time from the old ASVO to this new one to not get confused on which tube went where. I was going to order a new one direct from Watts, but then found this for less than half their SALE price. What a bargain!

RO system, Thank you thank you thank you!!!!! This stopped a small trickle of water through my water meterwhich was the answer to the puzzle I have been seeking for a year and 1/2. I thought it was a couple of other leaks I had found and fixed, but still the meter registered as moving. I never dreamed it was the water system. This part was original and 24 yr.s old. In turning off the water under the sink to change the last filter, I noticed the meter stopped. So I was thrilled to finally solve the on going problem and mystery, It costs a lot of money to hire a leak detecting company, so I figured I would eventually figure it out, and bingo this was it. So happy Amazon had the right part. It has been a process of elemination to accidentally run across this last piece of the puzzle since I did not know what this part did on the unit, but water was not going through the system after changing all the filters one by one, it came down to the shut off valve, the part I dreaded most on changing since it looked ominice and scary, but now I know all about the dreaded chore of changing everything on the unit and what they all do. I always wanted to ignore and out of sight out of mind when it came to this hard to get to and hard to undo to redo everything on this complex system. It takes alot of muscle as well as patience. I can now breath a sigh of relief, and feel a sense of accomplishment. This part which was the scariest ended up being the easiest of all the parts to change and now my 24 yr. old unit is like new again. I hope this helps someone else with the same problem, you live and learn. I will now be changing the filters more often since this experiance.Thanks again for having the parts I needed.