By Troy Ethen

Summary: As an effective complement to water softeners, resin bed cleaners are gaining wider use in the industry. With different types of cleaners available, it’s important to know when to use them. The following outlines some advantages resin bed cleaners may offer your business.


When you start talking about chemistry to most people, including friends and family, their eyes begin to glaze over and they look in the opposite direction. If you press them for their attention, you may get some story about how they got a “D+” in high school chemistry and don’t want to talk about it.

When you start talking to a water treatment dealer about ion exchange, grains of hardness and total dissolved solids, you have a pretty attentive audience. But when you venture into the realm of chelating agents, redox reactions and atomic valence, your reception isn’t much warmer than most people’s response.

Still, more often than not, discussions about resin bed cleaners are about the chemistry and not about their usefulness in business. Simply put, here’s the chemistry: Resin bed cleaners work as a reducing agent that change atomic valence of oxidized metals, putting them back into solution and removing them from the resin bed. But you don’t need to know exactly how that occurs any more than you need to know how Shout removes a grass stain. What you really need to know is how resin bed cleaners can benefit your business.

Using resin bed cleaners isn’t just good science; it’s good business. The customer gets reliable performance from a major household appliance and the water treatment dealer gets a recurring source of revenue.

When to use resin bed cleaners
Resin bed cleaners are designed to remove metallic foulants from the resin bed. They can be effective for a variety of metals, but iron is the predominant metal of concern. Basically, if you plan to soften and you have even a trace of dissolved iron, you should use a resin bed cleaner or the water softener will lose capacity.

Certainly, you can use iron filters or chlorination to remove iron. If you don’t need to soften the water, iron filters and chlorination are the best options. But if you are softening, why would you add chlorine if you don’t have a bacteria problem? And why would you use an iron filter if your softener can handle the iron levels?

Types of resin bed cleaners
Resin bed cleaners can be applied using drip feeders (continuous feed systems) or manually mixed and poured into the brine well before regeneration.

Continuous feed systems drip a viscous liquid into the brine well from a reservoir that attaches to the inside of your brine tank (see Figure 1). The resin is cleaned with each regeneration. Continuous systems generally use weak acids that dissolve iron by lowering the pH. These cleaners aren’t effective in removing iron fouling; rather, they are effective in preventing it. Therefore, if you know iron is present, continuous feed systems should be applied at the time of installation.

Manual application typically requires a powdered cleaner. Application involves pouring a solution made with the powder and softened water into the brine well and initiating regeneration. The manual cleaning should occur when capacity drops below desired levels or (preferably) on a routine maintenance schedule, every three to 12 months, depending on iron levels of the influent water. These powders are strong chemicals that react directly with the iron and put it back into solution. This manual cleaning can return iron-fouled resin to its original capacity in lieu of a complete resin change.

Iron removal and cation exchange
Two kinds of iron in water will be discussed here: insoluble (red water) and soluble (clear water). Water softeners will only remove clear water iron and typically treat up to 10 parts per million (ppm)—depending on the brand and model—when used in conjunction with resin bed cleaners.

Many people refer to insoluble iron as “bad iron,” but at least your customer knows it’s a problem. A water treatment professional is typically called to remove the iron before the customer runs a drop of water into their home. What’s so “bad” about that?

The irony here is that clear water iron is often called “good iron,” but “good” iron is the real problem. The homeowner may only realize they have clear water iron after they see red stains in the shower, toilet, dishwasher, etc. And if they don’t use a resin bed cleaner, they run the risk of staining with or without a water softener.

Water softeners remove iron the same way they remove hardness. If regeneration occurs frequently, iron is removed from the resin the same way hardness is removed. But “frequent” regeneration means two to three times per week, which usually doesn’t happen. If regeneration occurs weekly or less frequently, iron turns from clear to red on the resin bed the same way it does on the shower wall. No amount of sodium chloride is going to remove it. Over time, this coating gets thicker and thicker and takes up more exchange sites, and the water softener loses capacity to remove iron and hardness. At this point, manual cleaning is needed.

Your rural water business
Ultimately, the most cost effective way to remove iron and hardness is the installation of a water softener and use of a resin bed cleaner. This cost effective approach is good for your customer. And using resin bed cleaners is good for your business. Resin bed cleaners reduce warranty claims and increase service revenues. This is especially true for rural accounts.

Regardless of where you are in the world, you probably have some iron in well water sources. Therefore, resin bed cleaners will be a benefit to your business. The only question is “How?”

How you use resin bed cleaners depends on whether you have salt delivery and/or maintenance contracts. If you’re in the customers’ homes for salt delivery or routine maintenance, offering a “cleaning special” can increase your revenues and provide optimal system performance. It’s common to charge $50-$100 per cleaning, less if combined with other service. Cleaning is performed two to four times per year, depending upon iron levels. You would use continuous feed systems when the iron level is too high to justify frequent cleaning. As noted in Figure 2, continuous feeder systems and manual cleaning should be combined when iron levels are higher than 3 ppm.

If your business plan limits service and delivery to warranty and call-ins, you want to provide continuous feed systems in all cases. The last thing your business needs is service calls for fouled equipment. Homeowners are typically charged $15-30 for the feeder and $20-30 per gallon for cleaning solution (one gallon will last 100-200 regenerations). Assuming there’s iron in the water, it’s highly recommended you inform the customer that their performance warranty is voided unless they maintain this chemical supply.

Regardless of your service capabilities, if you’re called upon to replace a unit or the resin due to reduced capacity, try manual cleaning first. It’s a high-value, low-risk option.

Your municipal water business
Municipal water supplies are generally low in dissolved iron. Iron is typically removed as a result of the disinfection process. Nonetheless, you may benefit from resin bed cleaners when treating municipal water.

Iron stains occur in the home on a municipal supply when water stands in the distribution system, fire hydrants are flushed or when copper and galvanized pipes are directly connected. Iron problems are only temporary when introduced from the distribution system, but the treatment required is the same as with rural water. The problem is more likely to occur at the far end of older distribution systems. In these cases, it pays to do an annual cleaning, especially considering broader benefits of the sanitizing effects.

Copper-to-galvanized connections result in iron corrosion from electrolysis. You can eliminate your customers’ problems by installing dielectric unions. And after the problem is solved, you have an opportunity to sell resin bed cleaner to remove existing stains. Most household cleaners and detergents are too mild to effectively remove rust stains, but powdered resin bed cleaners work great to clean clothes, showers and toilets; the inside of washing machines and dishwashers; or any other iron-stained surface.

Cleans, disinfects…and deodorizes
An underutilized advantage of periodic resin bed cleaning is the resulting disinfection. The same chemistry needed to dissolve the iron also retards bacterial growth, and the chemicals aren’t as harsh on the resin and softener components as chlorine.

It’s well accepted that resin beds grow bacteria. These bacteria may not be harmful, but it’s good practice to disinfect the resin bed to reduce the risk of bacterial infection, and remove bacterial slime that reduces exchange capacity and increases pressure drop.

The disinfectant capabilities of resin bed cleaners are certainly not as good as chlorine; however, they will significantly retard bacterial growth (see Figure 3).

Conclusion
In almost all cases, the use of resin bed cleaners will improve the performance of a water softener. That’s the main benefit to you and your customer. The added benefits occur when you incorporate resin bed cleaners into your business plan to increase service revenues or reduce warranty costs. How resin bed cleaners fit into your business plan depends on your customer base and the service aspects of your business plan.

About the author
Troy Ethen is president of Spectrum Labs. He holds a bachelor’s degree in chemistry from Carleton College and has been working in the water treatment industry for 13 years, during which he has served on and chaired various Water Quality Association technical committees. He can be reached at (651) 633-0101, ext. 107, (651) 633-1402 (fax) or email: tethen@spectrum-labs.com

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