Rainbird’s residential series valves have a small internal filter which can become clogged with grit, even with reasonably clean water supplies. When this filter becomes clogged the valve will no longer fully close when operated automatically. Here’s how to clean the filters.
The reason for the filter is that Rainbird uses a very small port (water passage) for the water flow that helps to power the valve. A hydraulic solenoid valve is actually two valves. A tiny valve called a “pilot valve” is operated by the solenoid, this small pilot valve operates the larger valve. This allows a small 24 volt solenoid to open even a very large valve. The port in this model of Rainbird valve is smaller than those found in most cheap valves. There is a good reason for this, a smaller port makes the valve close slower and reduces water hammer. The trade off is that the super small port easily clogs up. To keep it from clogging, Rainbird has placed a small filter inside the valve. Unfortunately, eventually this filter becomes clogged up with grit too! When it becomes clogged the valve will not completely close. So it has to be cleaned. Most do-it-yourselfers will have no problems with this relatively easy repair.
Below are instructions and photos specific to the Rainbird DAS/ASVF, DV, DVF, CP, and CPF model valves (the repair kit part number is #DRK-CP.) The Rainbird DRK JTV/JTVF, JTV, JTV/AS and JTV/ASF “Jar Top” models use different parts but are very similar (repair kit part number #DRK-JTV.) The repair kits are optional, you may be able to fix the valve without buying new parts. Most other anti-siphon valve brands are similar enough that you will be able to figure it out.
Tools & parts: You will need a medium size Phillips screwdriver, a medium size standard flat-blade screwdriver, a toothbrush, and a small container or plastic bag to put the parts into so they don’t get lost. I like to also have a bucket handy to keep everything in so I’m not laying stuff in the dirt or mud. You may also need two new water-proof splice connectors if you need to cut the wires. If you want to replace the parts you will need one of the repair kits mentioned above and a very small flat-blade screwdriver. See links to example repair parts ads at the bottom of this page. Most of the time just cleaning the parts is sufficient to repair the valve.
Click on the photos to view the full size image.
Don’t panic over the number of steps here, I’ve broken it down into very small “bites” so that even a beginner won’t choke on it. 🙂
1. Turn off the water supply. Obvious, but hey, if you forget to do it you will get a face-full of water!
2. Fully open the flow control on the top center of the valve by turning it counter-clockwise. Tip: There is a screwdriver slot on top of the flow control in the center of the knob. I find it is easier to use a standard flat blade screwdriver to operate the flow control, rather than trying to turn the knob with my fingers.
Now open the bleed screw (the smaller of the two knobs on top of the valve) to release the water pressure in the valve, then re-close it. Turn it counter-clockwise to open, clockwise to close.
3. Remove the solenoid by twisting it counter-clockwise. You may need to cut the wires to do this. Make sure you leave enough wire to allow you to reconnect the wires later! In the photos I have already disconnected the wires.
4. On the bottom of the solenoid is a blue plastic screen. Use a toothbrush to clean it, rinsing it with lots of water. You don’t need to remove the screen from the solenoid, just clean the exposed surface. If you bought a repair kit, a new screen is provided in the kit. Pry the old screen out of the solenoid using the smallest screwdriver you can find. Be careful, it should come out easily. Do not wedge the screwdriver in and damage the soft plastic solenoid body or you will have to replace the solenoid!
5. Remove the silver screws from the perimeter of the valve lid and remove the valve lid by lifting it straight up.
6. After you remove the valve cap you will see the diaphragm with a spring on top of it.
7. Pull the spring off by pulling it straight up.
8. Once you get to the diaphragm in the Rainbird valve you will probably find it is stuck tight to the bottom half of the valve. Carefully and gently peel the diaphragm up by the edges and remove it.
9. On the bottom of the diaphragm you will see a little white plastic filter. Inspect the diaphragm carefully for cracks, tears, rips or any other damage. If it is damaged you need to get a repair kit, which will have a new diaphragm to replace it.
10. Use a toothbrush to carefully clean the filter and diaphragm. Clean all the other parts as well.
11. Turn on the water supply and flush out the valve. Turn it on very slowly so it doesn’t make a mess. Leave it on just long enough to be sure anything that might have fallen inside the valve body while the lid was off gets flushed out. Don’t skip this step! You may think nothing has fallen in there, but I’m telling you from experience there is a good chance something did and you don’t know it. Plus there is probably sand in the bottom of the pipes leading to the valve that came in from the water source and settled there. In the process of working on the valve that sand gets stirred up. It doesn’t do any good to repair the valve only to have sand go right back into it and wreck it the first time you run it! So take a minute to flush the pipes out now, while you have the lid off the valve.
Make sure the top of the valve body is clean, there is a groove in the top surface, make sure no dirt is in the groove. It’s easy to get dirt on this surface and not notice it when repairing the valve! The valve will leak if you have any dirt in the groove. It is really important that everything is clean when you reassemble the valve! I can’t over-stress this importance that everything be clean. You just cleaned the filters, you don’t want them immediately clogged up again!
12. Place the diaphragm back on the valve body, carefully align it so that the holes in it align with the screw holes in the valve body. The little filter plate you cleaned should be on the bottom of the diaphragm.
IMPORTANT: There is a ridge (like an o-ring molded into the edge) around the perimeter of the diaphragm, press the edges down so that the ridge fits down into the groove on top of the valve body. If you don’t get the ridge pressed into the groove you can damage the diaphragm when you screw down the lid!
13. This is the trickiest part of this repair. Place the spring inside the valve lid. There is a spot inside the lid that the spring fits into that centers the spring. If you do it carefully you should be able to get the spring to stick into the spring holder. If you can’t get it to stay there you may have to put the spring onto the diaphragm and just do your best to align the lid onto the spring. Now carefully place the lid so the bottom of the spring goes around the protrusion from the top of the diaphragm. Push the lid all the way down, if everything is properly aligned it should easily press on. Install one of the lid screws to hold it in place but do not fully tighten it. Just screw it in far enough to pull the lid down so that it just touches the body. When installing the lid screws turn the screw backwards like you are removing it until you feel it “click” into the existing threads. Then reverse direction to screw it in. The screws should go in easily, if not you missed the threads, try again. Do not force the screws in if they do not turn easily! Keep trying until you find the threads.
14. Insert the remaining screws, alternating from one side to the other. Again, do not tighten them, just insert them enough to pull the lid down against the body.
15. Now after they are all in go back and tighten them, again go from one side to the other. You need to alternate so you don’t warp the lid when you tighten the screws, if you warp it ti will leak. Now do a final check of all the screws to be sure they are all tight.
16. Screw the solenoid back on.
17. Close the flow control all the way by turning it clockwise.
18. Turn on the water.
19. Open the bleed screw, water will squirt out, that’s supposed to happen. Now slowly open the flow control, the water will start flowing through the valve. Close the bleed screw. The valve should close (don’t panic if it doesn’t.) If it doesn’t close, tap gently on each side of the valve a few times with your screwdriver, tap the top of the solenoid also, to force water back into all the valve cavities and passages. Try closing and opening the flow control and also the bleed screw a few times. Be patient, on occasion I have had to repeat this procedure 5 or more times before the valve started working correctly. When air bubbles become lodged in those tiny ports they can be very difficult to dislodge.
20. Reattach the solenoid wires to the control wires from the timer. Use waterproof connectors! The #1 cause of valve solenoid failure is not waterproofing the wire connections. Water is sucked up into the solenoid through the tiny spaces between the wire strands. Then the solenoid rusts inside and stops working. All the wire splices must be water-tight! You can purchase waterproof wire connectors at any hardware store. Follow the instructions on the package for installing them.