Case Study: Cooling Towers at Five Large Retail Branches — Condenser Approach Held Below 4°F for 24 Months
In the air conditioning systems of large buildings, chiller efficiency does not depend on the chiller alone. It also depends on the cleanliness of the heat rejection system, particularly the condenser and the cooling water system connected to the cooling tower. If scale, algae or biofilm begin to accumulate on the heat exchange surface. Even in small amounts, the chiller can consume more energy than necessary.
One of the key indicators building engineers use to track abnormalities in the system is the Condenser Approach Temperature, or approach value, which directly reflects the condenser’s ability to transfer heat. A low value indicates the system is still exchanging heat well. A value that rises steadily is usually a sign that the tube surfaces are becoming fouled, that scale is accumulating, or that fouling is developing inside the system.
This article presents a case study from five large retail branches that changed from conventional chemical water treatment to an ozone water treatment system in the cooling tower’s cooling water circuit, and were able to hold Condenser Approach below 4°F continuously for 24 months.
Case Study: Over 10 Million Baht a Year Saved with a Chemical-Free Ozone Cooling Water System
Managing energy costs in large buildings, particularly hospitals, which must run air conditioning 24 hours a day. Represents one of the principal unavoidable costs. One frequently encountered problem is the accumulation of scale, algae and bacteria inside the condenser and the cooling tower, which reduces heat transfer efficiency, causes the chiller to work harder and consume more energy than it should, and drives electricity costs higher.
This case study took place at Faculty of Medicine – Khon Kaen University, which chose to install ECONOWATT’s chemical-free ozone cooling water treatment system, model OZG 120 S, with real operating results recorded over a total of 730 days. The outcomes were clear across energy, financial and environmental dimensions.
Ozone Water Treatment for Chillers: Hospital Case Study
The cooling water system is a critical component that directly affects chiller performance. When scale, biofilm or algae accumulate inside the condenser tubes, heat exchange declines, the machine works harder, consumes more energy, and brings with it ongoing chemical and maintenance costs.
A leading hospital in Bangkok switched from chemical water treatment to the ECONOWATT Ozone Water System, model OZG209N5Y, to manage its cooling tower and condenser water. Comparative data was collected from October 2025 to May 2026. The result: the Condenser Approach Temperature of both chillers fell noticeably, with no condenser tube cleaning performed, and with the machines running at higher load than before.
Case Study : Corrosion Test When Utilising Ozone for Cooling Tower Water Treatment
The cooling water systemis central to both air conditioning and production processes in industrial plants. Where water quality is not properly managed, scale, biofilm and equipment corrosion can develop, driving up energy consumption, shortening equipment life, and raising maintenance costs.
Many organisations are now adopting Ozone Water Treatment as an alternative approach to managing cooling water: reducing chemical use, controlling microbiological growth, and maintaining the efficiency of cooling tower and condenser water systems.