Control Is The Key: Irrigation

The need for easy to use and easy to maintain irrigation systems has never been greater than now as the number of new system installations continues to rise and more landscape contractors are adding irrigation services to their mix.

The Irrigation Association estimates there are nearly 40,000 contractors installing more than 500,000 residential and commercial systems annually in the U.S., and the market continues to grow.

This growth has precipitated a manufacturing focus on simplifying the systems and their components, and this is most obvious with recently released controllers.

ON THE HOMEFRONT. “The real emphasis with controllers now is to make them simpler,” explained David Zoldoske, director at the Center for Irrigation Technology at Fresno State University, Fresno, Calif. “The capabilities of the electronics has really surpassed our abilities with the equipment. Now the manufacturers are making controllers more user-friendly for contractors, taking a lot of the popular commercial controller features and offering them to homeowners as well.”

Hunter Industries, San Marcos, Calif., developed the SRR remote control for use with its residential or light commercial irrigation systems. “The unit allows the contractor or the homeowner to turn zones on and off from up to 450 away from the controller and is small enough to fit in the palm of your hand,” remarked Jeff Carowitz, marketing manager.

The remote control includes a large LCD display and just four buttons — two for selecting the desired station or program and the on and off buttons, so anyone can use it. “There’s an outlet where the remote control communicates with the controller, and this can be located either inside or outside the house so homeowners don’t have to leave their house or garage open for the contractor,” Carowitz continued.

Don Thompson, vice president of sales and marketing, Rain Master, Simi Valley, Calif., said these remote controls are rapidly becoming considered a standard part of many systems. “The remote controls are being specified now by the designers because they think it’s important to make sure the maintenance people are checking the system regularly and this is one way to make that easier to do,” he said.

Carowitz said this type of system can also work to boost contractors’ sales efforts. “The units can be priced affordably enough so contractors can offer them as an added benefit to the customer. Plus, a lot of homeowners will enjoy being able to use this type of technology themselves. That makes purchas-ing a system even more attractive to them.”

Technology developed and implemented for commercial controllers is steadily making its way into the residential market, as Rob Nytko, product manager for the landscape and turf division of L.R. Nelson, Peoria, Ill., illustrated with that company’s SmartZone™ EZ unit. “We took a lot of the commercial programming features, such as a non-volatile memory, water budgeting and a moisture sensor hook-up, and we put them in a residential unit,” Nytko said.

COMMERCIAL BREAK. A key feature of the commercial systems is having the ability to add additional stations to a controller. Most controllers offer this capability, but the ease with which this can be done and the number of stations a controller can accommodate are important for a system’s cost efficiency.

Users of Nelson’s system need only purchase additional four-station cards to add to the controller. “The controller will still remember the old program, too,” noted Nytko, “so the contractor only has to program the new stations and not the entire system.”

Keith Miller, construction operation manager for Cedar Landscape Inc., Hillsboro, Ore., pointed to simpler programming as one dramatic improvement manufacturers have made. “Contractors used to only have two programs to choose from, but now there’s several programs,” he mentioned. “Not only can you tailor the program to the site now, but you can set a particular program for each specific area on a site, depending on the particular weather conditions.”

There is still room for improvement, however. “The ability to go up to a controller and quickly review the program really isn’t available,” Miller said. “If you want to see how long a zone is set to run, you have to go through the entire clock, and that takes too long. It would be nice to have a clock that you could scroll through, find the zone you want and change it.”

Nelson recently released the SoloRain series of DC-powered programmable solenoids which work as wireless controllers attached directly to the valve they control. “Contractors leave the solenoid right on the valve, and the big benefit is how they eliminate the need for long runs of pipe and wire between stations,” Nytko explained.

Controllers have definitely become tools to use for water conservation, as well as for system operations. “We are a water management company first,” noted Thompson. He explained that Rain Master’s RME Hawk Control System includes a feature that senses any electrical shorts in the system and automatically shuts off that valve without shutting off anything else in the system. “This way, contractors can immediately identify where the problem is, and the system keeps operating on schedule until there is time to make the repairs.”

Thompson said new controllers are also offering increased water monitoring capabilities to help contractors better understand how their systems are operating and identify any problems with them. “Contractors can hook a flow sensor directly to the system to record the flow,” he said. “This can then detect main line breaks and trigger an automatic master valve shut down to avoid any flooding or unnecessary water use.

“This is going to be even more important to contractors because the legislators are telling them they can’t waste water,” Thomp-son continued. “In that regard, property owners are also becoming concerned and are driving some of these developments.”

Miller said his company has found moisture sensors particularly valuable for water conservation. “We can set it up so the areas with north and east exposure aren’t irrigated, but the sensors in the south and west won’t block the system from activating,” he explained.

Carl Dowse, irrigation division manager for The Bruce Co. of Wisconsin, Middleton, Wis., said he regularly buys controllers with built-in rain sensor bypasses. “Having it already built in saves us about an hour in installation time and also gives the controller a cleaner appearance,” he said.

Seasonal adjustment switches can also prove valuable to contractors installing systems for someone else to operate. “These switches let us explain to the homeowner or client who will run the system that they no longer have to change length of time the system runs as the weather changes. They only have to slide the percentange switch to add or subtract run time from each zone,” Dowse remarked. “It’s much easier than teaching them how to program 16 zones.”

OPEN AND SHUT CASE. The greatest controller in the world is worthless, however, if the valves it controls don’t do their job properly when it comes time to turn the system on and off. Most manufacturers have a series of valves to offer contractors, but only a few of the manufacturers are emphasizing valves in their new product development right now. “All of the manufacturers felt they had to offer valves to call themselves full service,” explained Zoldoske. “The only real difference between them is that some have forward flow and some have reverse flow.”

Weather-matic, Dallas, Texas, has been incorporating reverse flow technology in its valves for years, according to Jim Goodrich, technical services manager. He explained that for a reverse flow valve, the water flows in the opposite direction than with normal valves, so that the outlet and inlet reverse roles and self-flushing porting eliminates the need to include a screen in the valve assembly. “Internally, the valve is designed so when it’s closed there is equal pressure on the top and bottom sides of the diaphragm wall,” Goodrich said. “Unequal pressure can start to cause some pinhole leaks in the diaphragm.

“The two main advantages of reverse flow valves are they can make the diaphragm last longer and if the diaphragm develops a tear, the valve will fail closed,” Goodrich continued. “The solenoid still goes on the downstream side, and unless you know what you’re looking at, you can’t even tell it’s a different type of system.”

Weather-matic has also added a manual bleed lever underneath the solenoid that will raise the actuator and alleviate the pressure when contractors have to manually operate the solenoid. “The water goes back downstream through the sprinkler so the valve box won’t flood and there’s no problem replacing the solenoid,” Goodrich added.

Zoldoske pointed to Olson Irrigation Systems, Santee, Calif., as one company taking an innovative approach with valves, although its new product won’t actually affect valve performance.

Olson’s multi-valve assembly units allows contractors to install as many as six valves in one standard sized valve box. In fact, the valves are purchased already assembled and factory tested so the contractor is only required to attach the unit to the water inflow and attach the controller wires.

“Normally, six valves need to go in two valve boxes,” noted Kathleen Baldwin, vice president. “All of the assembly takes place at the job site. This takes several hours, and contractors tell us that they usually only have one employee qualified to do the installation. This eliminates those problems.”

Don Olson, president and designer of the system, explained that when maintenance is required on one valves in the box, a central ball valve can be used to shut off water flow to all of the valves. “We included a quick disconnect bonnet assembly on top of the valves and plug-in solenoids so a contractor can pull the entire working mechanism out of the box to work on it,” he said.

Nytko predicted the emphasis on system control will soon influence new valve development. “Valves are becoming a commodity item,” he noted. “But in the future pressure regulation is going to be important for better efficiency and water conservation.”

Zoldoske also expects more attention to be paid to valves used for any irrigation systems with extremely low flows such as drip irrigation. “All of these valves don’t perform equally,” he said. “Some of the valves have had trouble shutting at low flow conditions like 1 gallon per minute.”

WIRE-TO-WIRE. Along with Olson’s valve assembly, Zoldoske pointed to Hit Products, Lindsay, Calif., and its two-wire system as a significant irrigation innovation.

“Now, a 42-zone system has a hot wire and a common wire running from the controller to each valve. The contractor ends up with a broad network of wires throughout the site,” explained George Cook, vice president. “With a two-wire system, the contractor would have two wires running along the system that would connect each valve.”

The wiring is the basic wiring and it is purchased as part of a system with a controller. “Each valve has a decoder connected to it with a standard 24-volt solenoid that tells it what valve it is,” Cook continued, explaining how contractors can still program a select valve or valves with a two-wire system. “The controller sends out a signal to the entire system to activate one valve, but that signal only matches with one decoder and that’s the only valve that turns on.”

Cook pointed out numerous benefits to two-wire systems. “There’s a significant wire savings in installation, but more importantly, contractors don’t have the liability of having all of that wire in the ground when a wire breaks,” he said. “The system is self-diagnostic because if the first 27 valves work but number 28 doesn’t, the break has to be between those two valves.”

With two-wire systems being cost efficient right now for systems of at least 12 or 18 zones, Cook sees a promising future for this technology. “Right now, contractors don’t trust two-wire systems because they’ve been doing it the other way for so long,” he said. “But I’ll predict that the future of irrigation is two-wire systems, and that future will be here in five or 10 years.”