Antifreezes are special compounds that are mixed with water in heat pump and other heating and cooling systems to prevent the water from freezing at low temperatures, ensuring that the systems operate smoothly even in cold weather conditions.
How does antifreeze work?
Freezing point depression: Antifreeze solution freezes at a lower temperature than pure water, thus preventing systems from freezing.
Maintaining heat transfer: Antifreeze maintains the proper thermal conductivity of the fluid, which is essential for the efficient operation of heat pumps .
Corrosion protection: The additives in antifreeze reduce the risk of corrosion and oxidation, protecting the system from material damage.
Types of antifreeze
Ethylene glycol-based antifreezes: They are very effective in preventing freezing, but they are toxic, so their use is only recommended in industrial or closed systems.
Propylene glycol-based antifreezes: More environmentally friendly and less toxic alternatives, often used in residential systems such as heat pumps.
Glycerin-based antifreezes: Less common, but a safe and environmentally friendly solution in certain systems.
Important information about the use of antifreeze
Correct concentration setting: The concentration of antifreeze in the solution must be adjusted to the intended operating temperatures of the system.
Example: In a system sized for -20 °C, an antifreeze concentration of 30–40% is usually required.
Maintenance: The effectiveness of antifreeze can decrease over time, so the freezing point and the condition of the additives should be checked regularly. It is recommended to replace antifreeze every 2-5 years, depending on how intensively the system is used.
Environmental considerations: Antifreezes must be handled and disposed of properly, as some types (e.g. ethylene glycol) can be harmful to the environment.
Safety precautions: When handling antifreeze, the product safety data sheet (MSDS) must be observed, especially when using ethylene glycol.
Summary
Antifreezes are essential for the safe and efficient operation of heat pumps and other similar systems. Ethylene and propylene glycol-based antifreezes are particularly popular as they protect systems from freezing, reduce corrosion and ensure heat transfer efficiency. For optimal operation, regular inspection and maintenance are required to maintain the effectiveness of the antifreeze solution and the longevity of the system. Environmental and safety considerations are also key when using antifreezes.