- 10/17/2024
- 9min
Functions of the radiator antifreeze
In addition to the engine oil, radiator antifreeze is one of the most important operating fluids in the engine. It ensures that the engine operates efficiently and reliably even under the toughest conditions. However, it not only protects the coolant against frost, as the name suggests, but also serves as year-round protection for the cooling system.
Cooling
Radiator antifreeze plays a crucial role in controlling the extreme heat generated during combustion and optimally protecting the engine from overheating. The radiator antifreeze increases the boiling point of the cooling water, which would otherwise evaporate quickly at these temperatures and burst cooling system lines. Thanks to its high thermal conductivity, it also ensures a constant operating temperature for the engine. The radiator antifreeze therefore plays a decisive role in the thermal management and cooling of the engine in both summer and winter.
Antifreeze
However, the radiator antifreeze also ensures that the coolant remains liquid at icy outside temperatures. It reduces the freezing point of the cooling water and prevents crystallization and expansion of the water, which would otherwise explode components in the closed cooling circuit.
Corrosion and cavitation protection
Without the use of the right radiator antifreeze, high temperatures and pressure differences can create ideal conditions for rust and cavitation (pressure due to vapor formation). Holes eat their way into the material and lead to damage to the coolant pump, cylinder head, cylinder liners and the cooler unit. This can lead to the complete failure of the cooling system.
Protection against water deposits and foaming
Tap water contains different amounts of minerals in dissolved form depending on the region. These transform when the water is heated and can become insoluble. This can lead to limescale deposits. This deposit significantly impedes heat exchange, which can lead to overheating of the engine.
Liquids have different tendencies to foam. This is caused, for example, by circulation or turbulence. The antifoam additives contained in the radiator antifreeze minimize the foaming of the coolant during operation.
Why does the coolant need to be changed?
Over the course of time the additives in the radiator antifreeze lose a part of their effectiveness and again make the system vulnerable to corrosion. Regular replacement is necessary to protect, maintain and clean the cooling system.
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Topping up or replacing radiator antifreeze: the right mixing ratio
Not every radiator antifreeze needs to be mixed. There are also ready mixes that can be added directly to the cooling system. Concentrated radiator antifreeze, on the other hand, must be diluted with water!
We recommend using distilled water to avoid limescale and other deposits in the cooling system. Depending on the water hardness and quality, dilution with tap water is also an option, but the water should not be too hard and not contain too many minerals. The water hardness should not exceed 3.56 mmol/l (20 °dH). (For information on your water quality, contact your local water supplier.)
We generally recommend a mixing ratio of 50:50. Our ready-to-use radiator antifreeze mixtures are also all set to a 50:50 mixing ratio. This ensures optimum protection of the cooling circuit against overheating, frost and corrosion. The proportion of concentrate can be higher or lower depending on the outside temperature and radiator antifreeze. However, it must be ensured that the proportion of radiator antifreeze is not less than 35 percent and not more than 60 percent.
The specific and exact mixing ratio is indicated on each product label.
Warning, risk of burns: be careful when refilling!
Make sure that you only check or top up the coolant when the engine has cooled down. If the engine is hot, there is a risk that the cooling system is pressurized and that hot liquid could be released when the cover is opened. This can result in injury or scalding.
Also, when adding cold coolant to a hot engine, temperature differences can cause cracks.
In addition, it must be noted that the volume of the coolant increases when heated. An example: If there is eight liters of coolant in a car and it is heated from 20°C (cold engine) to 100°C (warm engine), the volume expands by about 0.4 liters. It is therefore important to always check the level when the engine is cold and top up if necessary.
Why not just cool with radiator antifreeze?
Radiator antifreeze concentrates must never be used undiluted! The coolant only fulfills its functions optimally when mixed with water. If too little water is added to the coolant or if it is used undiluted, the coolant can freeze as low as -15 °C, for example. In addition to other complications, this can result in damage to the cooling system or engine.
Why not just cool with water?
Cooling using only water or an insufficient amount of radiator antifreeze is not sufficient! This does not protect the cooling system against frost, corrosion, cavitation, deposits or foaming. The consequence of these problems can be expensive system damage as well as major engine damage.
Why is it important to use the right radiator antifreeze?
Different engines and cooling systems require suitable operating fluids. For example, every radiator antifreeze has been developed for special requirements in order to be able to fulfill the aforementioned functions in the best possible way. If a coolant is used that does not comply with the required values, this cannot be guaranteed. In addition, the following consequences may occur:
Use of the wrong antifreeze can void the manufacturer’s warranty. Many manufacturers have specific requirements that need to be met. Use of an unapproved product may void the warranty on the cooling system and other affected components.
Different vehicles use different materials in their cooling systems, such as aluminum, rubber or plastics. Incorrect antifreeze can attack these materials, which can lead to leaks, corrosion or other damage. It is therefore essential to select an antifreeze that is compatible with your vehicle’s materials.
The correct antifreeze helps to comply with the recommended maintenance intervals. Some antifreezes have a longer shelf life and require less frequent replacement. Using an unsuitable agent could result in the need for more frequent maintenance and increase the service costs of your vehicle.
A general distinction is made between silicate-containing and silicate-free radiator antifreeze. If these two different technologies are mixed during refilling, the additive packages contained interfere with their effect. In the worst case, this will result in lasting damage to the engine.
If radiator antifreeze of different quality is mixed when topping up, the additive packages affect each other and there is less protection for the engine and the cooling system. It is possible to mix the coolants of various manufacturers but is not recommended.
For these reasons, the manufacturer’s specifications must always be observed when topping up or changing radiator antifreeze. In addition, it is advisable to use only high-quality radiator antifreeze products to ensure optimal operation of the cooling system.
Our modern radiator antifreezes are both high-quality and always comply with the manufacturer’s specifications.
Due to the high risk of mixing incorrect coolants, make sure that the coolant is completely replaced when replacing it. In addition, the cooling system must be cleaned before refilling to completely remove the old coolant and deposits.
What does the coloring of radiator antifreeze mean?
The color of the radiator antifreeze is only used for categorization and indicates the special additive composition required by different car manufacturers for different cooling systems. The products were specially coordinated with and tested on the materials fitted in the cooling system. The color is therefore only a small part of the manufacturer's specification and not a clear quality feature. It only serves to improve clarity. The color is not decisive for choosing the right radiator antifreeze – the corresponding manufacturer specifications must be observed!
Which radiator antifreeze is right for your car?
Only the manufacturer’s specifications are decisive for choosing the right radiator antifreeze. You can easily find out which is the right one for your vehicle using our oil guide.
With our wide range of radiator antifreezes, we offer the right product for every vehicle. As with all our products, quality is our top priority.
