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The integration of a chiller with a closed-circuit cooling tower offers a powerful dual-benefit solution.
It guarantees reliable, stable operation while maximizing energy efficiency. The core advantage of this system is its unique capacity to maintain strict water conservation standards without sacrificing operational flexibility.

Closed-circuit cooling tower + chiller unit: How does this golden combination deliver 1+1>2 performance?

Core principle: Heat transfer. 
In a cooling system, the chiller unit acts as the "dispatcher," chilled water and cooled water serve as the "transport vehicles" for thermal energy, and the closed-circuit cooling tower functions as the ultimate "radiator" for heat dissipation.
 

As illustrated in the diagram, the integrated cooling system operates in two primary modes, ensuring both operational reliability and optimal energy efficiency.

1. Conventional Cooling Mode (Chiller Operation)
During spring, summer, and autumn, the closed-circuit cooling tower is responsible for heat dissipation from the chiller's condenser. In this standard mode, cooling water circulates within a sealed closed loop through the tower's internal coils. Heat is efficiently rejected via external spray water and evaporative cooling, guaranteeing stable and reliable cooling system performance.

2. Energy-Saving Direct Supply Mode (Chiller Bypass / Free Cooling)
During winter and mild transitional seasons, when the outdoor wet-bulb temperature drops sufficiently (typically 3–5°C below the required chilled water setpoint), the system achieves significant energy savings by shutting down the power-intensive chiller. In this mode, water pre-cooled by the closed-circuit cooling tower is routed directly to air handling units or process cooling equipment. This operational strategy, widely recognized as "free cooling" or "cooler bypass," delivers substantial electricity savings while maintaining required cooling capacity.
 

In practical engineering applications, the following system configurations are commonly adopted based on specific project requirements：
Closed-circuit cooling towers paired with water-cooled screw chillers represent the most classic and widely adopted configuration in industrial cooling. Integrated with a PLC control system and precision sensors, this setup enables fully automatic year-round operation by seamlessly switching between conventional cooling mode and energy-saving direct supply mode based on real-time return water temperature monitoring.
 

Two core advantages

• Superior Water Quality Enhances System Reliability

Protecting Core Equipment: The heat exchangers inside chillers, including evaporators and condensers, are highly sensitive to water quality. With closed-circuit cooling towers, the cooling water circulates within sealed coils, preventing direct contact with air. This design fundamentally eliminates the ingress of contaminants such as dust, debris, and algae, effectively preventing scaling and corrosion on chiller heat exchange tubes. As a result, equipment service life is significantly extended, and high-efficiency heat transfer is consistently maintained.
Enabling "Free Cooling": The ability of closed-circuit cooling towers to deliver consistently clean cooling water makes them ideal for direct supply to air conditioning terminals or process equipment, thereby unlocking the potential of "free cooling" strategies. In contrast, open-circuit cooling towers often yield poor water quality, and introducing such water directly into terminal units poses significant risks of blockages and system damage
 

• Significant Energy Savings & Reduced Operating Costs

Drastically Lower Electricity Bills: The energy-saving direct supply mode is the cornerstone of the system's conservation capabilities. During winter, cooling demands can be met by operating only the cooling tower fans and spray pumps, dramatically reducing overall power consumption and resulting in substantial electricity cost savings.
Substantial Water Conservation: In contrast to open cooling towers, which suffer from significant water loss due to evaporation, drift, and blowdown,closed-circuit cooling towers consume far less water. This makes them an ideal solution for water-scarce regions or facilities aiming to reduce their water footprint.
 

Need more information on closed-circuit cooling tower systems? Reach out to us at sales@newinmachine.com for professional technical support and customized project solutions.