noise in the pipe fixed - would like to share my experience
Hello, I just joined. I had a similar noise problem after we installed a new sprinkler system around the 4th of July this year (2008). I googled and found this group, but it was too technical for me. I am new to sprinkler systems and decided to study a little bit and was able to fix our problem. Based on what I read here, I feel like my experience would help some of you or some future readers. I live in Claremont, California (35 miles east of LA). One day I realized the portion of the pipe connecting two values broke and I decided that it would be a good time to replace all the valves and the whole assembly. So, we bought six of Rainbird JTV/ASF-075 values and installed them successfully, we thought. When we tried each value (station) manually they worked well. We connected them all to the main controller and set the time to be 12:30am. They seemed have worked well - until about 3 weeks later. In the middle of the night (when station 6) started, the noise was so loud we thought the whole house was going to collapse. The noise was travelling between the area where the new values were installed which is in the front of the house and the back of the house where there is another set of four valves which are controlled by a separate controller. I went out and basically identified where the noise was coming from, but couldn't do much. I shut the controller down. A friend of mine suggested that it is perhaps because the water pressure in the middle of the night is too high, so try to water at a different time. So, we reprogrammed and let them run early morning hours instead, and the noise did not come back. So, we thought that fixed the problem. A few more weeks went by, but we noticed that two (stations 4 and 6) of the new stations had not been working, i.e., grass was dying in those areas. Plus the noise came back to station 6. I decided to learn a little bit about the values. I read the Rainbird manual and tried various things, which I would like to share. First, I tried to swap the controller wire from station 5 (which was working fine) with station 4 and verified that the controller is sending the signal ok to valve 4. Similarly control signal was working fine for station 6 as well. Both stations 4 and 6 worked fine when I tried the external bleed screw. So, I thought it must be that there is something wrong with either the solenoid or the diaphragm. By the way this particular value has three ways of controlling water flow through the value: (1) external bleed screw to manually turn it on or off; (2) the 'black knob' by which the amount of water flow can be adjusted; and (3) the solenoid that you can manually turn to turn the water on or off. As I said external bleed screw worked ok on both 4 and 6. For the 'black knob' that controls the amount of water I left all 6 of them fully open. Now the solenoid: this is where control wire is coming in from the main controller. Apparently the wire internally turns it on or off when it is operational. We can manually turn the solenoid without the electrical signal to turn the station on or off. So, I tried to turn 4 manually using solenoid. Aha, the water was flowing through the valve 4 so little that only one of the sprinkler heads was getting a little bit of water and all the other heads were not getting any. Similarly valve 6, there was no water at all reaching the heads. I concluded that the mechanism within the valve that controls the water flow was not working. I went to the store and bought two more valves of the same model. I swapped the part containing solenoid and diaphragm of valve 4 and a new one. Hey - station 4 worked now. Now on to station 6. With new parts installed on station 6, it was getting water alright now but the problem was that the NOISE came back!!! By sheer luck, a thought flashes by - perhaps there may be too much water flowing into the value? I decided to try to reduce the amount of water flow into it. Sure enough the noise went away. Whew...!!!... Without understanding fully why, the controller for the amount of water was open fully on all 6, but the very last one could not handle that same amount of water. So, the problem I think was that two of the original new values were not good or got broken. Trying a different amount of water flow through the valve makes a difference when it comes to noise (?). I am happy that I fixed mine at least for now. I am not sure if there is more fundamental problem that I did not fix such as water pressure, back flow control, hammer something, etc. etc. Before you spend a lot of money replacing/installing many of these, try something simple - you might get lucky like me. I hope this is useful for someone. I am a college professor (computer science) who did not know anything about sprinkler systems - just bought a house about a year ago, got interested in gardening, started replacing all the plants/grass with drought tolerant plants. Ended up learning a little bit about sprinkler systems. The previous owner was watering this garden every day - we are watering twice a week - our goal is to reduce it to once a week during the summer and none during the winter. - Ace.