28
October
2006
Drip Irrigation systems are primarily used to water non-grass landscaping, such as flower gardens, ground cover plants, trees, shrubs and vegetable gardens.
You can build your drip irrigation system onto your existing sprinkler system. When I design my system, I always plan on one extra valve on one of the valve manifolds to power the drip system. The main component that you will want to add when going out from your valve to the drip system line is a some type of pressure reducing valve to bring the water pressure down to around 25 psi. The parts of the drip system generally do not need, and probably will not tolerate a higher pressure, and unless your drip system is really, really large you will not need that much volume of water.
Usually you can get a kit, or at least some parts that go together to make the pressure reducer and a special filter. The drip system line and parts have smaller openings than most regular lawn sprinkler parts, and it is easier to clog. The filter will clean out extra particles that might clog the small lines, and you will want to find a filter that is easily removed to clean out and replace. It’s usually a mesh screen.
Depending on the brand of parts, there is a multitude of drip system parts and accessories. I usually run a 1/2″ poly pipe line around the main places where I will be using the drip system and keep it fairly shallow, and then run 1/4″ microtube out from the main 1/2″ line to wherever I want to water something. From the 1/4″ microtube you will be able to find all kinds of mini spray jets, drippers, bubblers and misters to name a few, but there are many. They are all pretty cheap but like most jobs with sprinkler systems, it adds up fast!
Once you get your valve, pressure reducer and filter, and the main 1/2″ line ran around the places you generally will be using the system, it is easy to go back and punch in the small 1/4″ line for the individual drippers and other parts as you go and as you add new plants.
I always set up the main 1/2″ line first and then add the 1/4″ lines to the plants when I can get to it, but once you have everything watering off of your drip irrigation system and on the timer, it’s a pretty nice feeling and very convenient.
Posted: Drip Irrigation
13
October
2006
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
11
October
2006
If you live in an area of the world where the tempurature is going to get below the freezing point of water for any amount of time during the winter, about now you need to be thinking about blowing out your sprinklers if you haven’t already.
You system may have line drains in it, which helps drain the water from your lines after each cycle of watering, but often this will not be enough, especially where it gets really cold in the winter. Line drains should be at the low points of you system if you have it to drain any water and avoid freezing inside the lines, but often some water may not all drain, or if you hook up your sprinkler heads from a side port, the bottom of the sprinkler will still have water that needs to be removed.
Blowing out your sprinkler system will involve using an air compressor with compressed air in place of water in your system to remove all the water out of the lines. When choosing an air compressor, you want one that can put out at least 10 cubic feet per minute, and can reach 50 psi. 50 psi is probably the maximum pressure you would want to use when blowing out your sprinklers. Your water pressure may be a little higher, but components usually do not tolerate the higher pressure of air as well as water since they are a different density. The minimum cubic feet per minute is just as important as the pressure. When you blow out each zone, you need a compressor that has the horse power or has a tank that can maintain the 50 psi pressure while blowing them out for a minute or two.
When I winterize my sprinkler system and blow out my lines I will connect the air compressor to a designated place as far up the line as possible, closest to the water source. When installing the system I will add a “T” to connect the air compressor fitting before my backflow valve. This allows me to use the air just as I would the water in the procedure to blow out the lines. Here are the steps I follow each fall to blow out my sprinkler system:
- Turn off your water source to the system, and go to your timer or manually open each valve for about 15-20 seconds to drain the pressure.
- Use what adapters you need to connect your air compressor hose to your sprinkler system, and a minimum before your control valves.
- Make sure all the valves are closed and turn on the pressure from you air compressor. This should pressurize your system just as the water would. If you have an above ground backflow preventor, it may make some noise as it tries to seal the main valve. You may need to help it a little with your finger if you can.
- Now go to your timer or to the valve manifold for each of the zones and turn on one zone. The sprinkler heads should pop up just like they would with water, and start spraying out water until it empties the line. Then it should start sputtering with air and water and eventually just air. If you compressor can’t maintain the volume of air you may have to close the valve and let the pressure and air volume build up in the tank again.
- Repeat this procedure with each valve (zone) until all the lines for all the zones have been blown out. Usually I will cycle through each zone 2-3 times to make sure they are dry.
- You can now unhook your air compressor, leave all the valves open, keep your timer plugged in and turn it to the “Off” setting so it won’t run the valves during the winter. Also be sure to leave your main water for the system off. This seems obvious but I thought I would mention it. If you turn the water back on, go back to step #1.
You can often find local landscape companies that will come out and winterize your sprinkler system and blow out your lines for you, and usually they will add you to the schedule to turn it back on in the Spring. This might not be a bad idea if you are uncomfortable with this procedure, and may not be much more than the rental of an air compressor.
Posted: Winterization, Procedures
