Boilers & cooling towers.

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What are boiler and cooling tower maintenance services?

Boilers and cooling towers are critical to maintaining heating and cooling efficiency across commercial and industrial sites. However, without proper maintenance, these systems can become breeding grounds for corrosion, scale, and harmful bacteria such as Legionella. Regular inspection, cleaning, and water treatment are therefore essential to safeguard performance, safety, and compliance.

At Complii, we provide comprehensive boiler and cooling tower maintenance services that ensure your systems operate efficiently and meet all regulatory standards, including HSG274 Part 1, ACoP L8, and the Water Supply (Water Fittings) Regulations 1999. From risk assessments and biocide dosing to corrosion control and system refurbishment, we help you manage water quality, reduce risk, and extend the life of your assets.

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Why choose Complii?

How we can help.

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Legionella prevention and compliance

Cooling towers and evaporative condensers are recognised as high-risk systems under HSG274 Part 1. Our maintenance programmes include cleaning, disinfection, and biocide treatment to control Legionella and ensure ongoing compliance.

Improved system efficiency

Regular descaling, chemical dosing, and corrosion control optimise heat transfer and water circulation, significantly improving energy efficiency and reducing operating costs.

Reduced downtime and repair costs

By preventing scale build-up, corrosion, and microbiological fouling, our proactive maintenance approach helps you avoid costly system failures and unplanned outages.

Tailored treatment programmes

Each system is different. We provide bespoke maintenance packages, including testing, chemical treatment, and automated control systems, designed to meet your site-specific requirements.

Environmentally responsible treatment

We use high-performance, eco-friendly treatment chemicals and water management methods to achieve efficiency and compliance with minimal environmental impact.

Expert support and clear documentation

All maintenance activities are supported by UKAS-accredited laboratory analysis, detailed reporting, and full audit trails to demonstrate compliance with HSE and environmental standards.

Your questions answered.

Cooling towers can accumulate scale, corrosion, and biofilm that restrict heat transfer and increase Legionella risk. Regular cleaning, disinfection, and water chemistry control are required under HSG274 and ACoP L8 to ensure safe operation.
The HSE recommends that cooling towers are cleaned and disinfected at least twice a year, or more frequently if inspection results indicate contamination or fouling.
Boiler water treatment prevents scale and corrosion through the use of chemical inhibitors, oxygen scavengers, and blowdown management. This keeps heat transfer surfaces clean and reduces the likelihood of tube failures.
Yes. We design and commission automated monitoring and dosing systems to maintain consistent water chemistry and reduce manual handling risks.
Absolutely. Legionella and total viable count (TVC) samples are taken regularly in accordance with ACoP L8 and tested in UKAS-accredited laboratories.
If sampling or inspection identifies contamination, we provide immediate corrective actions, including system disinfection, chemical rebalancing, and follow-up testing to confirm compliance.

News & insights

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Introducing Complii: A new chapter in building safety and compliance

For years, navigating the world of building safety and regulatory compliance has felt complicated and fragmented. You might work with one specialist for your fire systems, another for water quality, and yet another for electrical testing. It's a system that creates administrative waste, unnecessary risk, and makes it hard to get a complete, clear picture of your building's health.

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For businesses, this proactive approach helps reduce risks, avoid costly downtime, and demonstrate compliance with electrical safety regulations.

News / September 23, 2025

PH Water and Air Technologies joins Complii

We are pleased to announce that PH Water and Air Technologies has joined Complii. This addition strengthens our water and air compliance services and further supports our mission to provide trusted, integrated compliance solutions across the built environment.

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Compliance with confidence.

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