Chemistry Automation: Always in Command

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Although electronics to automate and control water chemistry in pools and spas have been around for decades, the technology and the way it’s used have significantly advanced in recent years. The impact is being felt on both the commercial and residential sides of the industry, benefiting consumers and professionals alike. From independent service technicians to operators of large-scale pool and spa facilities, the ability to monitor, record and control key chemical constituents has become nearly indispensable.

“Control system development has kicked into a new gear,” says Alvaro Mendoza, president of Commercial Energy Specialists in Jupiter, Fla., and board member on the Committee for the Model Aquatic Health Code. “Yes, some people are utilizing it today the same way they have for 30 years, but we’re seeing greater acceptance and people making more use of what’s available. They’re starting to understand the full impact and benefits.”


The reason for these evolutionary shifts, according to Mendoza, is an increasing awareness of water quality issues. As a result, consumers as well as industry professionals are recognizing that control and automation are the surest way to achieve consistent water quality and operational efficiencies.

“We consider it a baseline for every responsible treatment program on a property,” Mendoza says. “Without control, you’re just guessing and reacting.”

He is far from alone in that categorical belief in chemical automation. “Without at least the most basic level of automation and control, pool service is a completely reactive business,” says Steve Kenny, owner of SRK Modern Pool Solutions in Wainscott, N.Y. Kenny designs, builds and services both commercial and residential pools. All of them, he says, benefit from control technology to ensure consistent water quality.

RELATED: Key Misunderstandings and Problems in Pool Water Chemistry (Part I)

“You can’t be everywhere at all times to adjust for changes in water chemistry,” he says. “So, absent some type of chemical automation system, you’re always chasing the water conditions, whether it’s sanitizer and oxidizer levels or water balance. You become a hamster on a wheel, always running but never getting anywhere.”

Mendoza agrees: “If you wait for something to break in your car, then you are on the side of the road,” he says. “The whole concept of getting ahead of your maintenance schedule and knowing that a problem is starting to occur, that something is beginning to go wrong, that’s a very big deal. In general, people are busier now and they’re being asked to do more, so the more you can stay ahead of maintenance issues and respond to problems before they become bigger, that makes life easier and the systems far easier to maintain.”


Certainly, the mainstay of chemical automation has been, and remains, pH and ORP control. The tandem has been integrated into systems by all control manufacturers and has been applied to a range treatment scenarios, such as ORP’s use in controlling different types of chlorine feeders and generators as well as ozone generators. Likewise, pH control is widely used to add CO2 and/ or acid to correct changes in pH.

“The basic pH and ORP control, which is really still the base of chemical automation and control, hasn’t changed that much,” says Mendoza. “But the way it’s used, as well as the understanding and comfort level have advanced.”

Kenny is among those who have evolved in the way he applies control technology. He’s a proponent of using ozone and UV combined with small amounts of chlorine. To control this three-pronged system, he deploys a number of sensors, including ORP sensors after the ozone injection points and then downstream of the UV unit. The ORP shoots up after the ozone is added and then drops significantly once water passes through the UV chamber.

“It’s fairly theoretical and we’re still learning more and more about it, but what we believe is happening is the UV is turning the ozone into hydroxyl radicals by way of advanced oxidation process. Measuring the ORP before and after the UV chamber is the only way to indicate AOP is taking place. We know for sure that when the water leaves the ozone unit, it will have an ORP reading of 800-to-850 millivolts. After it passes through the UV unit, it has 300 to 350.”

While such sophisticated applications and interpretations could spell significant advancements in maintaining quality water, more commonplace applications should be a fixture in virtually all pool and spa systems, Mendoza says. “If you can’t take direct control of pH and ORP there’s no way to manage water quality,” he says. “Your Langelier Index will be bouncing up and down, which can lead to all sorts of problems. Chlorine consumption and all aspects of water quality will be inconsistent.”


Advancements in automation and control technology have moved in a couple of key directions: more control points and dramatic advancements in generating logs and notifications. In addition, Mendoza says, “We can now monitor alkalinity, which we never could before, and we can directly monitor and control chlorine based on parts per million, and we can monitor TDS.”

RELATED: Key Misunderstandings and Problems in Pool Water Chemistry (Part II)

He’s also quick to add that other key control points throughout the entire system will also have an impact on water quality as well as energy efficiency and operational efficiency. “You can monitor and control circulation rates, water level, water consumption, chemical inventory in the tanks, filtration cycles — there’s a wide variety of things you can control,” Mendoza adds. “You can be there on almost the entire equipment pad, where all the systems should work together to create the same result.”

“Controlling water quality isn’t just about the chemistry per se,” Kenny says. “It takes an entire holistic systems approach, which includes the hydraulics, filtration cycles and the physical cleaning by service techs and facility staff. It even involves the types of finish materials you use, which can influence water balance. Arguably it all starts with the water chemistry, but all of those pieces need to work together.”


Perhaps the most significant improvement to chemical automation and control systems is the dramatically improved logging and notification features. Most systems, both for residential and commercial pools, include features that create running logs of testing data and many have the capability of pinging the service professional or pool operator when something steps outside of the normal operating parameter.

“Alert notifications can help across the spectrum,” Mendoza says. “There are any number of scenarios where you’d want to monitor multiple locations at the same time. Maybe you’re managing rental properties or running a large service route, or maybe it’s hotels and resorts, or it could be parks and recreation people who are running more and more facilities. So often people are asked to do more and more these days.”

“Now you can look at your fl at screen in the morning and see where you should direct your efforts,” he continues. “You can focus on the biggest fire first and prioritize your work. Before, without that capability, it might take you all day to get around to 10 pools where you may or may not discover the problem. You can head off problems before they develop because now you’re in touch with all of your pools at a glance. That’s a big change that has come of age in the last 10 years.”

Kenny sees the ability to monitor multiple sites as one of the most empowering developments ever to hit the service industry, making the servicer more of a conductor than a laborer.

RELATED: CYA, pH, and Pool Water Treatment Realities

“These are outstanding systems that enable you to monitor many pools from one screen remotely, and they deliver the added benefit of email and text alerts,” he says. “All the systems have protocol adapters that will report to the one main screen, some allowing you to monitor up to 100 pools on one screen. The upshot is you can have a broad overview of all the pools with detailed information and helpful data. Also, each site has a history log that allows you to drill down to fine-tune the system and dosing style. You’re able to better predict what’s going to happen in the future because you can now accurately analyze the past.”


Mendoza believes that chemical automation and control systems will be more and more integral as the future unfolds.

“My crystal ball is saying, even though being in control has been pretty darn good for the last 20 years, it’s only going to improve. This is where we’re headed. We’re going to see intuitive behavior by the control system, helping you decipher the data. You’ll see the leading companies making improvement in manipulating the data and you’ll also have more data points, pumps, filters, water levels etc. It’s going to spread out over more parameters with different ways to mine and evaluate the information these systems provide.”

“It’s a true game changer,” Kenny says. “Even though it might seem as though that technology has been around for quite a while, the fact is those applications are continuing to develop in capability. Ultimately, this is how we’ll take control of water quality and consumer experience because we’ll be able to leave and less and less to chance.”

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