A Practical Guide to Glycol Chiller Systems: Understanding Design, Control and Installation

Understanding Glycol Chiller Systems

Across the UK, glycol chiller systems support industries that rely on accurate temperature regulation. From breweries and dairies to laboratories and manufacturing plants, these systems provide stable and controlled cooling using a glycol-water mixture as the heat transfer medium.

Unlike standard water chillers, glycol chillers use a mixture of propylene or ethylene glycol combined with water. This makes them suitable for processes requiring sub-zero temperatures and environments subject to low ambient conditions.

At a fundamental level, glycol chiller systems remove heat from a process and transfer it away through a refrigeration circuit. The cooled glycol solution is then pumped through pipework to absorb heat from equipment or products before returning to the chiller.

How a Glycol Chiller System Works

Effective system design ensures consistent output and reduced energy consumption. Core components typically include:

• Refrigeration compressor


• Heat rejection condenser


• Evaporator heat exchanger


• Metering device


• Integrated buffer tank and circulation pump


• Electrical control system

Within the evaporator, the refrigeration cycle extracts thermal energy from the secondary fluid. The chilled solution is then sent to the process load, absorbs heat, and flows back to the unit.

A typical glycol chiller system diagram shows two distinct circuits. The refrigeration loop manages heat removal, while the glycol loop delivers cooling to the equipment or product. Accurate schematics are valuable for installation, servicing and fault finding.

The Control Panel: Managing Performance and Safety

The glycol chiller system control panel acts as the central interface for monitoring and adjustment. Modern panels typically include:

• Programmable temperature regulation


• PLC or microprocessor interfaces


• High and low pressure safety switches


• Circulation pump management


• Alarm notifications


• BMS or remote access integration

The control panel manages compressor cycling, supervises operating conditions and ensures safety limits are maintained. Many systems also log performance data to support service planning and operational records.

In facilities requiring precise cooling, reliable control prevents temperature drift that could affect product quality or equipment integrity.

Installing a Glycol Chiller System Control Panel

Proper glycol chiller system control panel installation is essential for consistent performance and regulatory compliance. Key factors include:

• Electrical compliance – The panel should be installed in accordance with UK standards, with correct breaker sizing and safe isolation points.


• Location and ventilation – Panels should be located in dry, well-ventilated areas away from excessive heat, vibration or moisture.


• System validation – Qualified engineers should verify sensor calibration, test alarms and confirm pressure switch operation.

Commissioning ensures the unit operates in line with the original glycol chiller system design specifications.

Key Factors in System Design

Effective glycol chiller system design begins with detailed analysis of process requirements. Engineers evaluate:

• Required temperature range


• Hydraulic design and circulation requirements


• External temperature influences


• Redundancy or backup requirements


• Future expansion potential

Correct sizing is essential to avoid inefficiency or inadequate cooling. Load calculations must consider maximum usage scenarios and continuous duty patterns.

Fluid selection also plays a role. Propylene glycol is commonly used in food and beverage settings due to its lower toxicity, whereas ethylene glycol can be chosen for applications prioritising thermal performance.

Additional considerations such as pipe insulation, pump specification and heat exchanger configuration influence stability, efficiency and lifespan.

Applications of Glycol Chiller Systems

Glycol chiller systems support numerous sectors across the UK, including:

• Breweries and distilleries


• Dairy and food processing facilities


• Pharmaceutical production environments


• Laser and medical equipment cooling


• Plastics processing and injection moulding


• Cold storage and preparation areas

For example, in beverage production, chillers regulate process temperatures and stabilise product storage. In manufacturing settings, they protect equipment from excessive thermal build-up.

Protecting System Performance

Routine maintenance supports consistent output and equipment longevity. Typical servicing tasks include:

• Checking glycol concentration levels


• Assessing circulation components


• Cleaning condenser coils


• Verifying control panel settings


• Monitoring refrigerant pressures

Over time, glycol can degrade or become contaminated, reducing heat transfer efficiency. Regular testing helps maintain optimal performance.

When correctly designed, installed and maintained, glycol chiller systems can provide reliable service for many years.

Common Queries About Glycol Chiller Systems

What is the typical glycol percentage?

The required percentage depends on freeze protection and operating temperature, commonly ranging from 20–40%.

Is external installation possible?

Outdoor installation is possible when the system is designed for external conditions.

How does a glycol chiller differ from a water chiller?

Unlike water-only systems, glycol-based chillers resist freezing and support sub-zero applications.

Is remote access available?

Many contemporary glycol chiller system control panels integrate with BMS platforms or secure remote systems.

What is the recommended testing frequency?

Fluid condition should be reviewed regularly based on system workload.

Which industries benefit most from glycol chillers?

Industries requiring stable and low-temperature control frequently depend on glycol-based systems.

Final Considerations

Glycol chiller systems deliver reliable and consistent temperature control across a broad range of industrial and commercial applications. From accurate load calculation and correct commissioning through to routine servicing, every stage affects efficiency and longevity.

Whether planning a new installation or upgrading existing equipment, working with experienced specialists ensures compliance with UK standards and operational requirements. For technical advice and tailored solutions, consult the Newsome glycol chillers page to explore engineered glycol cooling solutions designed for long-term performance.