Cracked or broken pipes and valves that fail are common problems that need to be dealt with in a sprinkler system. In this piece I will cover the tools, parts and details of fixing these problems.
It takes some simple tools for these repairs, namely a shovel, PVC pipe saw, PVC glue and primer as well as the parts needed for each job. While most of these repairs will require some digging there are some way's to cut down on the amount needed. The main way is in the choice of parts for the repair. All the repairs discussed in this article are for PVC systems, gallivanted pipes will be covered at another time.
The easiest repair to deal with is a cracked or broken pipe in a strait section. After clearing enough room to work on the pipe you need to measure the area to be repaired. Here is where one of those parts I mentioned comes in. The part is called a slip fix or expansion coupler although it can go by other names.
Expand the slip fix and measure the exact distance that needs to be cut from the pipe and replaced by the slip fix. When everything is ready cut out the broken section of pipe. Once that is done follow the directions on the primer and glue to prepare the parts for reassembly. If the slip fix does not span the full area of the repair, a section of pipe and another coupler may be needed.
Repairs to broken fittings are harder to deal with because you sometimes have to cut out good fittings and rebuild the section. This is fairly common when fittings such as tees and elbows are set close together. It can also be a problem when replacing valves or an adaptor to those valves.
Valve problems are a little easier to pinpoint the cause. Water seeping from a head or a valve that will not shut off are a sign that the diaphragm in the valve is the trouble. A valve that fails to activate is a sign that the solenoid is bad or that there is a wire problem. In the first case replacing the diaphragm can sometimes cure the trouble but replacing the valve is always a possibility.
A harder problem to deal with is a station that fails to come on. Before getting to frustrated with how to find the cause there are two main suspects to check. The first is all the wire connections. Even in the best conditions corosion or rodents can break a connection. The next thing to check is if there is power to the solenoid of the valve. If the solenoid is buzzing but the station stays off the solenoid is most likely bad and should be replaced. If the solenoid is silent there is probably a broken wire.
At this point I will mention that one of the simplest tools I use for testing wiring is one of rain birds encapsalated solenoids. Simply touching the wires to the contact points will cause the solenoid to click if power is present. This works for both wiring and clock terminals.
While these are the most common causes of problems they are not the only ones. I hope these answers will give you a starting point in dealing with your sprinkler system.
Michale Holmes has been designing and repairing both residential and commercial sprinkler systems for over twenty-five years. As well as having extensive experiance in all fields of landscaping from construction to maintenence he is also the author of The Homeowners Guide to Sprinkler Systems which can be found at http://mrhirrigation.com