Water To Grow

Sprinkler System Valve Manifold0

A valve manifold can sometimes sound like an intimidating phrase to someone dealing with a sprinkler system for the first time, but as complicated as it may sound, it’s really not that bad.

I don’t think any one part of a sprinkler system is every really complicated, but if something was this might be a litte more so than others. All a valve manifold really is, is a way for the water coming from the main line to be regulated with valves, and split off into the different zones.

In laying the pipe for your sprinkler system you will have a main line that comes from your water source. This line will have live water pressure on it all the time, but you don’t want it sending water to the sprinkler heads all the time, and you don’t want water to go to all of the zones all at once, either. (You probably don’t have that much water pressure and flow.) The valve manifold splits off that main line into multiple (usually 3-5) zones, and when it splits off to each zone, the water pressure will meet a valve on this manifold. Each valve on the valve manifold (if automatic) will have two wires that hook up to your timer so that the timer can activate your valves when you would like and send water to one zone at a time.

Most residential yards will have two sets of valve manifolds, one on each side of the house. The main line just runs across one manifold and on to the other before it stops. This manifold will almost always sit underground in a valve box. Usually I would build my own manifold using either poly pipe with T adapters and claimps or PVC pipe with adapters and glue and then make threaded adapters for the valves to thread on to, but you can also buy pre-made valve manifolds that have all the parts and are molded to what you need with different numbers of branches available. (The valves are ususally sold seperate.)

Posted: Valves

BackFlow Preventors Are Your Friend0

A backflow preventor valve assembly is a pretty common part of any sprinkler job. If you are watering your lawn with the same water that you drink or use for other purposes you want one of these, and in most cases the law requires it. This valve is to ensure that any chemicals that are on your lawn do not flow back into the common water system from your sprinkler system, so really it’s an elaborate one way valve.

This valve in usually installed as the first part of your sprinkler system and is where all the water that feeds the system will come from. The pictured backflow preventor is called a Pressure Vacuum breaker. It is commonly used so that your valve is visible and accessable above ground. With this type of backflow preventor, you always want to make sure it is installed at least 6″ above the highest sprinkler head in your system so no gravity feed can passively go back into the system.

There are a number of different backflow preventor styles, some of which include the Reduced Pressure,  Atmospheric and the  Double Check. All of these will usually require yearly inspection by your city or local government.

Posted: Valves