Question
I have recently installed 14 of these heads, 7 per zone on brand new vales that were conveniently dead ended in my existing vault. My problem is that on each zone I get a couple of heads that just won't pop up on tier own and during each watering cycle I have it manually raise them before they will operate on their own. It's not always the sane heads and the pressure seems to be ample to run it all but I just can't Be here for every watering for this to work out long term for me.

I do have an extra zone I could use bur I just don't think this if going to resolve the problem. If you have any suggestions on how I can tune this system in I'd very appreciative of your help. I did flush the system out before installed the nozzle and rechecked the problem heads since then for debris, no dice.

I have to be missing something since the rest of the system works perfectly but I just can't figure it out. Any help would be very appreciated. I could even trade off information or parts for AV/Computer or network problems since this is my profession.


Thanks,

Joe Pitcock  

Answer
Hey Joe, I hope this helps. It could be a number of issues, but I'm going to assume that the system has been installed properly. By this I mean that you haven't put on too many heads or better yet your GPM(gallons per minute) that each zone is pulling is not too great for the amount of water GPM that you are receiving. The reason I'm going to assume this, is because it sounds like if you pull up on a head, it pops up fully and works fine. The heads you have installed the SAM-PRS series, are different from regular heads, in that they have check valve and regulator built into them, and require 25 Plus psi(pounds per square inch) to operate properly. The regular Rainbird  1804 series, only require 15 psi. You could try replacing the heads with the regular series, or repipe using the third valve, and only putting 5 heads on per zone. Let me briefly explain how a system is designed. The first thing you need to know, is how many GPM (gallons per minute) the valves are putting out. ONe way is to open the valve up, and while it's running, check your water meter, and after 1 minute, how many gallons has the valve put out. If you're not hooked to a water meter, you can use 2- 5 gallon buckets, and when you turn on the valve, stick a bucket at the end of the pipe, and fill up the buckets, and estimate how many gallons of water the valve put out, after 1 minute (thus gallons per minute). NOw you need to determine how many gallons per minute each one of the heads you installed, are using(GPM). You will need to get a chart on the nozzle sizes (or go online to www.rainbird.com) and get the nozzle chart. Each nozzle puts out a different amount of water (GPM). For instance, a nozzle size of 15H ( 15 foot spacing, 180 degree spray) will put out from 2 to 3 GPM. A 15F nozzle ( 15 foot spacing, 360 degree spray)will put out from 4 to 6 GPM. Lets say you have 7 heads each putting out 2 GPM(gallons per minute). Your valve will have to be putting out at least 14GPM ( 7 heads times 2GPM =14GPM). Lets say you have 7 heads that are each putting out 4GPM. Your valve will  be able to put out 28 gpm (7 heads times 4GPM=28GPM). You also need to pipe the system correctly. By a rule of thumb, if you use 1/2" PVC pipe, you can run between 4 to 6 GPM, for 3/4" pipe, you can run from 8 to 12 GPM, for 1" pipe, you can run from 15 to 20 GPM. Not knowing the size nozzles you have installed, the size of the pipe, and how many GPM the valves are putting out, it would be hard to pinpoint exactly the cause of your problem. Let me know if I can be of anymore help. Good luck and have a great day.