Recently I had the “pleasure” of seeing multiple point source emitter manifolds blow out on a property, all from the same manufacturer and under ideal pressure. Considering so many properties are converting spray irrigation to drip irrigation I thought this would be a good opportunity to try out a couple manufacturers’ products and see which offers the best flow options, installation ease and withstands the overall test of time.
Typically I try and stay away from ¼” tubing as an option. ¼” tubing can be hard to maintain with heavy landscape maintenance going on around the web of lines, but in tight planters there really is few other point source options. Almost every major manufacturer offers a manifold or some form of point source emission device as this is a very efficient way to get water to the root system at a consistent measured rate.
General Point Source Emitter Manifold Observations
The centralized ½” female thread seems to be the go to method of attachment for all these devices, from a design perspective this forces the installer to place unsightly valve boxes throughout beds and can further complicate maintenance. Removing a valve box to replace numerous valves is one thing but to replace a manifold that waters 6-8 plants in my opinion can be overly time consuming.
My recommendation to manufacturers is to eliminate the need of disrupting the valve enclosure by providing side outlets on the manifold not downward facing outlets and a flush valve of some sort for testing and flushing. Ideally with the prominent use of this technology a manifold based valve box design would be perfect!
One outstanding benefit of this device; ¼” valves allow the user to turn off certain emitter lines, which helps make the product a little more usable with different sized applications. Note: They come in the off position. The tubing was easy to push onto the barbs and held well after activation. Also, the tight footprint left room in the valve pit for easy identification of the ¼” tubes being used.
One challenge I experienced was the inability to open the manifold for flushing and testing. Also, the valve idea is great; however turning them with wet, dirty hands in close quarters is a little difficult. A flow range of 0-20 GPH sounds high to me on the high side of the range but durability seems high because there are no threads that can fail; only molding seams.
The resilient design helps keep the product in tact when attempting to make one of its many adjustments. Along with flathead shut off valves there are also threaded caps to eliminate soil and snail clogging. One challenge is there may be too many adjustments and these could confuse the layman. Also the threads that hold the caps on make it difficult to install the ¼” tubing. I like the individual flow adjustments with this product and the durability is good.
Rain Bird Xeri-Bird Multi Outlet Emission Device
First and foremost the ability to open the top and flush the device, as well as access through the top also uncovers a replaceable filter that helps prevent clogging. The ¼” tubing went on with ease and overall durability was definitely the best of all three products. This is by far the best and most expensive option, which makes sense. One potential challenge could be the separate emitters have to be installed inside the manifold to control flows. However the emitters also double as a Rain Bird point source emitter so inventory is minimal.
In conclusion, and in my opinion, what may be true in most industries is not always true in irrigation. More expensive does not always mean better quality…in this case it does.