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Concerned about Legionella in your water system? Delta Cooling Towers help reduce Legionella risk while eliminating the rust and corrosion common with traditional cooling towers.

Delta designed its Anti-Microbial Cooling Tower Shell to resist Legionella growth in water systems. According to Delta Cooling Towers, test results from Special Pathogens Laboratory, The Legionella Experts, demonstrate that Delta towers display the only anti-microbial efficacy against Legionella bacteria among common cooling tower construction materials. Special Pathogens Laboratory tested Legionella pneumophila Serogroup 1. The laboratory evaluated Delta compounded HDPE, FRP, and stainless steel, measuring bacterial counts after a 24-hour incubation period.

Compare Delta’s Results with Other Common Cooling Tower Materials:

Cooling Tower Shell	Anti-Microbial Efficacy
Delta AM HDPE	Yes
Stainless Steel	No
FRP	No
Anti-Microbial Fill	Yes
Standard Fill	No

Facility managers must reduce maintenance, prevent corrosion, support water treatment programs, and minimize Legionella risk. Delta Cooling Towers address these challenges with a unique combination of non-metallic HDPE construction, anti-microbial technology, and innovative basin design. At Kerr Pump & Supply, we help customers select Delta Cooling Towers that deliver reliable performance, longer service life, and lower maintenance costs.

Download Delta Cooling Anti-Microbial-Brochure

Download frequently-asked-questions

Walk through many industrial facilities and you’ll see cooling towers showing signs of rust, corrosion, and years of wear. Traditional galvanized steel towers are constantly exposed to moisture, chemicals, and outdoor conditions. Over time, corrosion can lead to higher maintenance costs, repairs, and shorter equipment life. Rough, corroded surfaces can also encourage biofilm buildup, making an effective water management program more challenging.

Delta Cooling Towers are different. Their seamless, non-metallic high-density polyethylene (HDPE) construction will not rust or corrode like traditional metal cooling towers. That means a cleaner appearance, reduced maintenance, and long-term durability—even in demanding environments.

Many traditional galvanized cooling towers eventually require repainting, coating repairs, or panel replacement due to rust and corrosion. Delta’s seamless HDPE construction eliminates these common maintenance concerns, helping facilities reduce long-term maintenance costs while maintaining a cleaner appearance. Years after installation, Delta Cooling Towers continue looking clean and corrosion-resistant, while many galvanized steel towers begin showing rust, staining, and deterioration.

Long-Term Cooling Performance

Key advantages include:

• Non-metallic HDPE construction that won’t rust or corrode
• Anti-microbial HDPE shell compounded throughout the material
• Excellent resistance to aggressive chemical water treatment
• Reduced maintenance and longer equipment life
• Reliable performance in harsh industrial environments

Reduce Legionella Risk

Minimize Stagnant Water in Cooling Towers

Stagnant water creates an environment where microorganisms can thrive. Delta Cooling Towers incorporate several design features intended to keep water moving and help reduce biofilm buildup:

• Anti-microbial PVC or polypropylene fill and drift eliminators
• Aggressive side-to-side basin slope
• 3% slope toward the outlet
• Optional basin sweeper systems on select models
• Designs that help minimize standing water

By helping inhibit microbial growth on the HDPE shell itself, Delta’s anti-microbial construction helps reduce one of the surfaces where biofilm can develop. Combined with proper water treatment, routine cleaning, and a comprehensive water management program, these design features support efforts to reduce Legionella risk.

Delta Cooling Towers vs. Traditional Metal Towers

Feature	Delta HDPE	Traditional Metal
Rust Resistance	✓	✗
Corrosion Resistance	✓	✗
Anti-Microbial Shell	✓	✗
Chemical Resistance	Excellent	Moderate
Maintenance	Lower	Higher
Long-Term Appearance	Stays corrosion resistant	Rust and deterioration over time

Why Choose Kerr Pump & Supply for Delta Cooling Towers?

Whether you’re replacing an aging galvanized cooling tower that has begun to rust or planning a new installation, Delta Cooling Towers provide a long-term solution designed to minimize corrosion, reduce maintenance, and support reliable system performance.

As a trusted Delta Cooling Towers representative, Kerr Pump & Supply helps customers select the right cooling tower for new installations and replacement projects. Our experienced team can evaluate your application, recommend the best solution, and provide the support you need to improve reliability and reduce long-term operating costs.

Frequently Asked Questions

What is Legionella?

According to Delta Cooling, Legionella is a type of bacteria that can cause serious lung infections, including Legionnaires’ disease. It grows best in warm water environments and can spread to humans when tiny water droplets or mist containing the bacteria are inhaled. Cooling towers can provide conditions where Legionella may grow if they are not properly maintained.

Why are cooling towers associated with Legionella?

Cooling towers operate with warm water and create water vapor, making proper water management essential. According to the CDC, many Legionella outbreaks have been linked to water systems, including cooling towers used in commercial HVAC systems and industrial process cooling. Proper system design, water treatment, monitoring, and maintenance are critical to reducing risk.

What conditions promote Legionella growth?

Legionella is more likely to grow when the following conditions are present:

• Poor water circulation and stagnant water, particularly in cooling towers with large flat-bottom basins
• Water temperatures between 68°F and 122°F
• Water with a pH between 5.0 and 8.5
• Sediment that promotes the growth of commensal microflora
• Microorganisms such as algae, Flavobacteria, and Pseudomonas, which provide nutrients or harbor Legionella

What helps prevent Legionella growth?

Reducing Legionella risk requires a comprehensive water management program that includes:

• Proper chemical water treatment using oxidizing biocides, as recommended by Delta Cooling (while recognizing these treatments can be aggressive toward metal cooling towers)
• Cooling tower designs that minimize stagnant water through sloped basins and optional basin sweeper systems
• Routine inspection, monitoring, cleaning, and consistent maintenance

According to the CDC, approximately 5,000 cases of Legionnaires’ disease are reported each year in the United States, making proactive water management an important part of cooling tower operation.

How does Delta’s anti-microbial shell differ from a surface coating?

Delta’s anti-microbial protection is compounded throughout the HDPE material rather than applied as a surface coating. Because it is integrated into the shell itself, it does not wear away like surface treatments and remains part of the cooling tower throughout its service life. According to Delta Cooling Towers, testing by Special Pathogens Laboratory demonstrated anti-microbial efficacy against Legionella pneumophila Serogroup 1 when compared with other common cooling tower construction materials.

Do Delta Cooling Towers rust?

No. Delta Cooling Towers are manufactured from non-metallic HDPE, so they will not rust or corrode like galvanized steel cooling towers.

Can a cooling tower prevent Legionella on its own?

No. No cooling tower can prevent Legionella on its own. Proper water treatment, routine monitoring, cleaning, and maintenance are essential components of a comprehensive water management program. Delta’s anti-microbial materials and tower design help support these efforts by helping reduce conditions favorable to microbial growth.

Ready to Upgrade Your Cooling Tower?

If you’re replacing a rusted cooling tower or planning a new installation, Kerr Pump & Supply can help you find the right Delta Cooling Tower for your application. Contact our team today to request a quote or speak with a sales engineer.

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