When shopping for a cooling system, you might notice a strange phenomenon: low-temperature chillers are always significantly more expensive than ambient temperature units. Is this simply due to arbitrary pricing by the vendor? The real cost difference lies in the equipment’s design details, material standards, and low-temperature technology. This article will help you understand the technical reasons for the high cost of low-temperature chillers.

What is a low-temperature chiller?

The outlet water temperature of ambient temperature chillers generally ranges from 5°C to 25°C, while that of low-temperature chillers can drop as low as -40°C. Some high-performance models can reach temperatures as low as -80°C or even -150°C. These low-temperature devices are primarily used in the pharmaceutical, chemical, and laboratory low-temperature testing industries.

Achieving low outlet water temperatures is a technical challenge. To ensure the equipment operates properly at temperatures exceeding several tens of degrees Celsius, its materials, structure, and refrigeration circuits face challenges that ambient temperature equipment cannot handle.

Why are low-temperature chillers more expensive?

What design differences do low-temperature chillers employ compared to ambient temperature chillers that contribute to their higher cost?

Special Compressor Design

Low-temperature operating conditions place even higher demands on compressor performance, as they must operate stably and long-term under low suction pressures and low temperatures. Conventional compressors experience lubrication failure and a sharp drop in efficiency at temperatures below -40°C.

Low-temperature chillers, however, are mostly internationally renowned compressor brands and feature specialized low-temperature designs. To prevent the lubricating oil from freezing, the crankcases are heated.

Furthermore, these compressor components are made of special alloys and feature high-precision bearings and seals, making them less susceptible to brittle cracking at low temperatures. However, these components are inherently expensive, and some chiller manufacturers import them from international markets, further increasing the overall price of the unit.

Complex Refrigeration System

Conventional chillers require only a single stage of compression to cool water to 5°C to 10°C. Low-temperature chillers, however, must reduce temperatures to -80°C or even lower. To avoid the safety risks associated with excessive compression ratios, multi-stage compression or cascade refrigeration technology is required.

Multi-stage compression uses multiple compressors to reduce the temperature in stages, with each compressor responsible for compressing the refrigerant to a specific temperature range to avoid excessive compression ratios. Cascade refrigeration connects two refrigeration systems in series, with the cooling capacity generated by the first system used to cool the condenser of the second.

This technology can reduce the outlet water temperature to ultra-low temperatures (below -80°C). Both of these refrigeration system designs require more components, such as compressors, heat exchangers, and expansion valves, and are more difficult to manufacture.

Higher Insulation Standards and Freeze Protection

Low-temperature chillers’ piping, evaporators, and liquid storage tanks are exposed to low temperatures for extended periods. Poor insulation of these components not only reduces capacidade de arrefecimento but also leads to severe frost or even ice formation on their surfaces.

Therefore, chiller manufacturers use materials such as rubber-plastic insulation and polyurethane foam as insulation layers, and install heating tape in key locations. The increased use of insulation materials and process steps increases the cost of low-temperature equipment.

More Precision Control Systems

Low-temperature chillers operate at extremely low temperatures, requiring extremely high control precision for temperature, pressure, and flow. While conventional chillers may have a temperature control accuracy of ±0.5°C, low-temperature chillers often require ±0.1°C or even ±0.01°C.

This is only possible with equipment equipped with high-precision sensors, PID algorithms, and programmable controllers. This control system not only has high hardware costs, but software development also requires significant time, naturally resulting in a higher overall system price.

More Safety Devices

Low-temperature environments pose significantly greater risks to equipment operation than normal temperatures. Therefore, low-temperature chillers are equipped with more comprehensive and sensitive safety features, such as high and low pressure protection, refrigerant leak detection, antifreeze protection, and oil temperature and pressure protection.

While these protections may not be used regularly, they can prevent expensive repairs and production downtime in the event of an anomaly, contributing significantly to the high cost of low-temperature chillers.

Low temperature chiller brings better user experience

The higher price of low-temperature chillers comes at the expense of more stable temperature control, faster cooling rates, and more reliable safety features. Low-temperature chillers are an excellent choice for equipment and processes requiring precise temperature control.

If you’re considering a chiller system for a new project, LNEYA is happy to provide you with professional low-temperature cooling solutions. From selection to installation, LNEYA can help you address various temperature control challenges in both testing and production.

Contact us today to discuss your cooling needs.

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