First, I would like to congratulate you on choosing a Rotary nozzle over a standard spray nozzle. In many cases, they are a superior choice over spray nozzles. They save water because they are more wind resistant. They use what Rainbird calls Multi-stream technology or I like to call fingers of water project through the air.
These fingers work well because they are constantly changing occasionally to water close and then another one comes along that waters far away. Their streams of water are more wind resistant than sprays keeping the water on target instead of on the sidewalk or on your car. They also have more even watering or uniform coverage than sprays, which has the potential to save water.
R-Vans like all other brand rotators have a lower precipitation rate than spray nozzles, meaning they put down the water more gradually allowing the water more time to soak in before running off. And lastly Rotary nozzles with their fingers of water look so cool!
Note:
Rainbird’s Rotary nozzles have changed since they first came out in the early 2000s. Originally, they came only in fixed patterns such as ¼ circles, ½ circles, full circles etc.
Now Rainbird has moved away from that system to what we now call Variable Arc nozzles they call R-Van Rotary Nozzles. There are some advantages and some disadvantages to the system but
In my experience, the durability and ease of use of the nozzles have improved.
These newer nozzles no longer need tools to adjust the distance of throw which is adjusted by hand by just turning an adjustment collar on the side of the nozzle. The nozzles now are more easily cleaned of clogs by gently pulling up on the nozzle by hand. This works for most clogs but not all. If too much sand or debris has entered the nozzle from the water source that could still wreck the nozzle beyond repair. So flushing the water supply lines before the nozzles’ initial installation is important.
Which Nozzle to Select?
Now that you have decided on using Rainbird rotary nozzles the next decision is selecting the best size nozzles for the job. First, you must measure the area you intend to cover. Then look at the selection of different nozzles that are available. The following chart shows a sample list of different Rainbird R-Vans available.
For the most recent list check out the ones at Rainbird.com https://www.rainbird.com/products/r-van-rotary-nozzles
1) Coverage Area
Now that you have decided on using Rainbird rotary nozzles the next decision is selecting the best size nozzles for the job. First, you must measure the area you intend to cover.
There is one more thing to keep in mind when selecting nozzles and that is “head-to-head coverage” . This may not be a concern to you if you are just replacing a broken nozzle in an existing system that was working properly before the repair was needed. So, if that is the case you may skip down a few paragraphs.
Then look at the selection of different nozzles that are available. The following chart shows a sample list of different Rainbird R-Vans available.
For the most recent list check out the ones at Rainbird.com https://www.rainbird.com/products/r-van-rotary-nozzles
Head-to-Head Coverage
Irrigation manufacturers design their Heads to be used in a system of multiple heads that overlap each other. Head-to-Head Coverage is the industry standard meaning each head sprays back to the other so the overlap is not partial but complete. The tempting pattern that some use to save initial cost on installation, but costs more in the long run, is called “pattern to pattern” coverage
The problems with pattern-to-pattern coverage are that the system is only as good as it’s weakest link, so if you have an area only covered by one nozzle the system will have to be run long enough to put down enough water to cover the single coverage area while the overlapping areas get twice as much water. Not to mention that many nozzles don’t throw down water evenly alone and many put less water down close to the head.
Fortunately, rotary nozzles are the best at uniform coverage and dry spots close to the head are less of an issue than most others, sprays, or rotors. Another problem with pattern-to-pattern coverage is there is no redundancy meaning if one nozzle plugs up the lawn has no back up head hitting that area as in “head-to-head coverage”, so the lawn starts dying. Wind is also more likely to cause coverage loss on “pattern-to-pattern” coverage than “head-to-head coverage.
Note: Head-to-Head Coverage is mandated in some States and Municipalities.
2) Size and Shape
Circular Pattern
Each Model is color coded to throw a certain distance. For example, the light blue (model R-VAN14) has a range that is specified to throw water as low as 8ft all the way up to 14 ft. The beige (model R-Van 18) throw is 13 to 18 feet and the burgundy (model R-Van 24) and throws the water a distance of 17 feet to… you guessed it, 24 feet.
Each Model also comes in at least two different patterns of coverage. For example, one is designed to have an adjustable arc pattern from 45 degrees to 270 degrees or in simpler terms 1/8 circle pattern to ¾ circle pattern. The adjustable arc models, for some reason, are not officially built to do smaller patterns than 45 degrees or larger than 270 degrees. So, if you need a full circle pattern you would use a dedicated 360-degree pattern nozzle in one of the three distance ranges you need. For example, if you need a full circle nozzle with an 8-foot distance you would get a R-VAN14-360 which can be adjusted down from a 14-foot maximum distance to 8 feet.
Strip Pattern
Now what if you need to cover an area that is longer and narrower than a square? Rainbird has you covered, pardon the pun, with its “Strip Nozzles”.
These nozzles are designed to cover some but not all long narrow areas. Unfortunately, there is not a nozzle for every size and shape so we must do our best to find the closest fit and hope that with adjustments we can get it to work.
Note: Read to the end of the article for a tip on how to cheat if you can’t find a nozzle small enough.
I like to design the landscape to match what is available for nozzle patterns but realize that is not often an option for most landscapes.
Note:
Another thing to consider when using Rotary nozzles is the spray body or head itself. It is recommended and even mandated in some States that spray bodies/heads with Rotary nozzles on them have a build in pressure regulator. These spray heads are known as PRS.
Rainbird recommends that R-Van nozzles be used with a PRS-45 spray body to regulate the pressure down, if it is higher, to around 45psi which is best for optimum efficiency of these nozzles.
Here is where I tell you a secret. If you need to water an area that is even smaller than the nozzles available by the manufacturer there is a way to cheat. If you need the nozzle to throw just one less foot or so. Use a 30psi-regulated head PRS-30 or PRS spray body which is commonly used for standard spray nozzles. Rotary nozzles will still operate at 30psi just with a shorter distance than usual.
So now with the information in this article and in our video “Rainbird R-Van Rotary Nozzles Adjustments” you are ready to select the best R-Van Rotary Nozzles for your job.
Congratulations!
So now with the information in this article and in our video “Rainbird R-Van Rotary Nozzles Adjustments” you are ready to select the best R-Van Rotary Nozzles for your job.
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