Aquatic Pros Talk Equipment

Aquatic Systems & Mechanical Design Considerations

Much like the wizard behind the curtain who controls the fabulous city of Oz, the equipment that makes aquatic areas fun, safe and energy-efficient is hidden while it creates the magic enjoyed by so many.

The pump room houses heaters and chlorination systems, secondary infection treatment and yes, pumps. These are essential, but for swimmers, exercisers and instructors, their presence is better unseen and unheard. Like a good sports official, aquatic equipment is working well when you don't notice it.

Decision-makers, operators, facility managers and maintenance folks do have to know about this technology: what to choose for a new facility; what to choose when it's time to replace; how much energy can be saved; how air and water can stop making the public sick; and what are the latest developments.

Two manufacturer executives and a certified service technician recently shared their thoughts on what facility professionals should know about pumps, heaters, chlorination systems, secondary disinfection, efficiency, sustainability and safety of water and air. Mike Fowler is commercial manager of a Cary, N.C.-based manufacturer of pool products and solutions for filtration, water treatment, maintenance and more; Charlie Luecker is director of commercial sales for a California-based manufacturer of commercial pool equipment; and Steve White is president of a pool company and a certified instructor and technician.

How has commercial pool equipment changed in the past decade?

White: Environmental concerns, in general, and concerns for energy alternatives, in particular, keep pools running with less energy cost—these are all changes that have happened over the past decade or two. Variable speed pumps can be adjusted to make required turnover rates while also saving energy. The goal is conservation of energy, water, chemicals, etc. What is good for business is also good for the environment.

Fowler: With more people focusing on health issues and climate change, the pool industry has moved in that direction in making sure aquatic facilities are running as smooth as possible and as clean and healthy as possible for all swimmers, whether competitive or leisure. More and more products have also become much more efficient, and at the same time automated, so it's made operating a facility a little easier than before.

What should aquatic operators know about pool pumps?

White: Pool pumps have changed drastically over the last few years. Technological advances are now making it possible for pool pumps to be more energy-efficient by adding variable frequency drives to the pool pumps or by changing out older single-speed pool pumps for new variable speed pool pumps. In either case, aquatic facilities use less energy to obtain the required turnover rate of the pool water and by using less energy they are also able to reduce their operating costs. So, facilities need to be made aware of the many benefits both in cost savings, improved filtration and ultimately additional savings in chemicals as well as improved water quality.

Luecker: Most jurisdictions now require dual speed pumps for energy efficiency. Having the ability to ramp down the speed of your pool circulation pump improves your facility's energy efficiency. Additionally, there are also variable frequency drives (VFDs) that allow the adjustment of the power supplied to the pump and adjustment to the pump scheduling to reduce operating costs. Some new pumps up to 5 horsepower are designed to include a frequency drive along with high-efficiency motors that can help reduce pump operating costs up to 90%.

Fowler: [They should] know how to size them correctly, know what's needed for installation, know what proper maintenance is for the pump.

What should operators know about pool heaters?

Luecker: There are three types of swimming pool and spa heaters that run on propane and natural gas: atmospheric units, which are standard air induction heaters; sealed combustion Low NOx heaters; and new high-efficiency heaters. The efficiency ratings on these types of heaters vary from 82% efficiency up to 98% efficiency. Low NOx units are now required to comply with increased air quality standards in some areas.

Fowler: [They should understand] what heaters are best for the application they have, and what's involved with properly performing heaters—flow, gas pressure, ventilation—and also how improper chemistry and ventilation can cause great damage to a heater.

White: Just like newer pool pumps, newer heaters are now also designed to be much more efficient.

Aquatic facilities can also reduce operating costs by upgrading to a new, high-efficiency heater. Older models from seven to 10 years ago may have started out being about 78 to 85% efficient. However, over time, the same heaters will only be about 60% efficient, as heat exchanger tubes fill with buildup and the burners get clogged too.

That said, newer models have higher efficiencies. Today's heaters range in the low-to-mid 90% efficiency range, and some direct-fire models have efficiencies up to 95%. As a result, these units consume less energy and will immediately lower electricity bills. Additionally, newer heaters are easier to operate and produce lower emissions, resulting in better air quality in the pool environment.

Builders today are more energy-conscious in their construction of commercial pools. In my opinion, heated water is best returned to the bottom of the pool instead of the top of the pool, since heat rises and quickly disappears if it is returned just three feet below the water line. So, heaters work harder and longer if the heated water isn't returned to the bottom of the pool.

In my opinion, this is a design flaw that we find in many commercial pools. But designers are getting better at creating more efficient systems of heating, and even if a facility is simply replacing an old heater with a new pool heater, the higher-efficiency heater will heat the water better and use less energy doing so.

What should aquatic facility operators know about chlorination systems and automation/controllers?

Fowler: [They should understand] the proper size of pool is in reference to the capacity of the controller. Make sure operators are aware of what local health departments want for chemical levels. Know about maintenance of the systems. If they're using a salt system, make sure to check with local jurisdiction to see what the requirement is for salt chlorine output per thousands of gallons of water.

White: Chlorination systems need to be supported by complete automation. Traditionally the industry has used pH and ORP (oxidation reduction potential) controllers, which are essential to run commercial pools indoors or outdoors for consistency of control and keeping a well-run pool when you may not have an operator looking at it all the time.

Today there are even more technologically advanced controllers that control pH, ORP and more, and these controllers adjust chemicals as bather loads change and chemical levels fluctuate. Some states require these controllers, and in my opinion, controllers are truly a must for commercial aquatic facilities.

What should aquatic operators know about secondary disinfection?

Luecker: Secondary disinfection systems treat pool water supplementally through systems like ozone, ultraviolet, and new advanced oxidation process (AOP) hybrid systems. All of these systems will improve overall facility water quality, and some will help reduce chemical consumption by lessening the demand for the addition of the sanitizers.

Fowler: [You need to understand] when it's needed and what products qualify through the National Sanitation Foundation as a true secondary sanitizer.

White: Ozone and UV is a trend and a change that has come into our industry. They are both very valuable choices for commercial and public pools. Contamination of pool water with known illnesses such as Cryptosporidium and Giardia make it essential that pools and spray parks have a strong secondary disinfection system as an added second layer of consistent protection.

They are not separate from sanitation using chlorine or bromine, but very essential for big commercial pools. This is particularly important with a high bather load. These systems work behind the scenes and not only improve water quality but also help combat the poor air quality caused by chloramines in these same pools with high bather loads.

What are some of the systems that will help aquatic facilities operate more efficiently?

Fowler: Using more energy-efficient pumps, such as those with built-in VFDs or high-efficiency heaters, will help the facility operate more efficiently. Making sure you're getting the most energy-saving potential out of your equipment and maintenance program will aid greatly with a facility operating efficiently.

Luecker: Heaters, pumps, VFDs and supplemental treatment technologies, as mentioned before, and the use of a chemical controller will help to consistently maintain the chemical residual in the pool or spa water. The use of a pool cover will reduce the radiation of pool heat into the air for an outdoor pool and into the indoor air in an indoor facility. The use of an automatic vacuum will reduce the need to use staff to spend time vacuuming your pool. These units usually pay for themselves in less than a year.

What kinds of systems improve indoor air quality?

White: Air quality is an essential part of indoor aquatic facilities, especially those with higher bather loads. UV systems actually help reduce the gases that come off the top of the pool, which are the result of the oxidation in the water. These gases cause real problems for competitive swimmers in particular. Breathing in these gases can be very detrimental to the health of athletes. Therefore, UV is an excellent way to help improve indoor air quality and there are several other ventilation systems in the marketplace that focus on removing those poisonous gases from the water surface to help protect the lungs of swimmers from this bad air on the surface of the pool water. Newer pools have ventilation systems specifically to remove that gas from the surface of the pool water. Humidity is also a problem that needs to be considered; ventilation systems need to remove this humidity so that you don't end up with rain in the indoor pool, especially in the winter.

Fowler: Make sure your ventilation in the indoor room is proper, and the air handling system is sized right for the indoor pool facility. Adding UV systems to combat chloramines is a big step in helping to eliminate the chloramines in the air that cause so much trouble to guests.

Where does sustainability fit in?

White: YMCAs, health clubs, municipal and public pools and recreational facilities offer a healthy lifestyle—it's an essential business in our world today. If these commercial aquatic facilities are going to continue to provide swimming facilities, which are an invaluable form of exercise and play to our communities, then these facilities need to be upgraded and renovated with equipment that will allow the facility to operate sustainably.

Not only does this equipment require less energy to operate the pool but also requires less water to be used—so they help save water. Conservation of water and newer equipment functioning with less backwash water are going to be required to sustain aquatic facilities over the long run. Newer filters are also now using less backwash water—traditional sand filters use a tremendous amount of water to wash the filters.

Water is at a premium at many parts of the country. Water rates are increasing just as electrical rates are increasing. If we want to have enough water for pools and enough drinking water, we need to waste less water in our aquatic swimming industry. Additionally, conserving water quality is essential, both in the pool and the water that is returned to the system through cleaning, etc.

What kind of energy cost savings can operators expect from the latest equipment?

Luecker: Energy-efficient pumps with a VFD can save up to 90%. The use of a VFD with your circulation pump can save up to 80%. Pool heaters are 82% efficient for the standard atmospheric heater, 85% efficient for a condensing heater, or up to 97% efficient on the sealed-combustion, high-efficiency units. The use of a pool cover can save from 50 to 70% on an outdoor pool and 25 to 30% on an indoor pool.

Fowler: With pumps using energy-efficient variable speed drives, whether built in or not, I could see as much as 60 to 70% savings, depending on applications and size of pumps. In most cases, these pumps can be slowed down in non-operating hours to aid in the energy savings factor. Heaters in the past were only sending 78% of their heat back to the pool, and some heaters of today are sending as much as 96%. So, based on that, an older model 400,000 BTU heater may have only 312,000 BTU going to the pool, whereas a high-efficiency heater of today would be sending as much as 384,000 BTU back. That lowers heating times and operating costs.

White: More energy-efficient equipment must meet the challenge of keeping operational costs in check so the facility can operate cost-efficiently and provide the benefits of swimming to the community that uses the pool. Manufacturers have risen to the challenge and provide energy-efficient variable speed pool pumps, which by the way, are being mandated after July 2021 by the Department of Energy.

Variable speed pumps also help improve water quality and clarity by dialing in the flow slow enough for the filter to do its job better. Variable speed pumps and variable frequency drives run the pump longer and slower so the filter works better.

What does the future hold for commercial pool equipment?

Fowler: Although you'll always have to have an aquatics service manager on site at an aquatic facility, the modernization of swimming pool equipment in the past years and in future years will help make their lives a little easier to maintain their given facilities and possibly use the savings in operation for other items or programs within the aquatics center.

Luecker: Energy efficiency and helping customers to reduce the costs to operate a facility is always the goal. Improvements to chemical delivery systems and supplemental disinfection systems for operators to run a cleaner facility is good for patrons. Anything safety-related, much like the Virginia Graeme Baker (VGB) Act that helped with suction entrapment and drain safety, would be a focus to improve facility safety.

White: The key word is change. What worked 10 years ago doesn't work today. Today it's efficiency and consistency. New regulations will force these changes. These efficiency improvements in today's aquatic facilities are essential. But even without regulations, aquatic facilities have been focused on reducing operating costs, and in doing so are actually also reducing the amount of chemicals they use, conserving water, using less electricity. By controlling speed they save electricity and still make the turnover, which ultimately allows filters to work better so water quality improves. All of these factors are key to the future. RM