Question
Hi James,

I would like to install more and change some of the irrigation heads in my builder installed irrigation system. I am totally new at this and would like some guidance. Could you please give me step-by-step instructions on how to go about this, ie. Shut off water at main, cut, glue, etc.

Thanks for your help.  

Answer
Maria,changing the heads will be easier than adding heads,so lets start with that. I doubt if you will have to shut off the sprinkler main off to change heads. Only valve in head systems (golf course,athletic field) require that you shut off main. So,identify which heads you want to change out and at the same time try to figure out where you want to add your heads. Mark them with  flags or sticks. Now,make sure the controller is off.(you don't want it to kick on while you're working. You get to do a little digging now. Dig up the heads about 6-8 inches down and you will see that they are simply screwed into a 1/2" or 3/4" fitting. They will either be on a riser (a piece of pipe staight atop the lateral) or swing pipe (a smaller hose about 1/2" that connects to a larger (usually 1") pipe. Now, unscrew the old heads and see what happens. Some of them will drain,some of them will suck air,and some of them will do nothing depending on how elevated that particular line is. The key here is to keep debri out of the lines and heads while you do this. On the ones that look like they are going to drain,like the lowest head at the bottom of a hill, you may want to dig a little extra deep under the head to provide a sump hole for the drainage water to fall in from which you can bale or pump out. Now,screw in your new head(some people put a wrap of teflon tape on the male threads,it's a good idea,but you can get away without doing it. The people that installed it probably did not.) Follow the manufacturers instructions on the new heads. They should be flush with grade,packed,and set either to the right or left stop depending on the type of head. The right and left stop applies mainly to rotory heads. Most spray heads don't make a difference about the stop. As far as adding heads hopefully some of the ones you are replacing will be in a convenient spot to tap into the line and add. If not find the closest head to the area which you want to cover and dig it up. See what kind of pipe it is connected to. If it is on the smaller swing pipe hose,you can often pump two heads off of this pipe with good pressure. Cut the hose and install a tee and run it to where ever you are going with the new head. You might not have enough flow/pressure to push another head off of this smaller hose,so it would probably be best to leave it unburied until you test it. If your system is really maxed out you might not be able to add a head anywhere. The swing pipe fittings should start with a wiggling motion and then spin or thread in the rest of the way. If you have to connect to the larger pipe (1"), if it is black you will need a poly saddle or tee (the saddle is easier to put on and doesn't require you to wrestle with the pipe,but is more likely to leak,so get them tight. If the pipe is white and hard you will need a pvc glue saddle. You will have to glue it, let it set,then drill a hole. That's it,sounds easy? You will probably end up running for parts after you find out what kind of pipe you've got and how much you need. You will need a couple of inexpensive tools to cut the pipe and install the saddles. The parts person at the suply house should be able to set you up with that. As always, feel free to write again if you have more question Thanks,Jim