Mineral Oil in Water Cooling: Pros and Cons Revealed in 5 Steps

The use of mineral oil in a water cooling loop is a topic of interest for many PC enthusiasts, but it is not recommended due to several technical reasons that can impact the performance and safety of the cooling system.

Lower Heat Capacity

Mineral oil has a lower heat capacity compared to water, which means it can absorb less heat per unit of mass before raising in temperature. The specific heat capacity of water is 4.182 J/g°C, while the specific heat capacity of mineral oil is around 1.9 J/g°C, approximately 54% lower than water. This reduced heat capacity means the mineral oil will heat up faster, requiring more frequent cooling, and ultimately reducing the overall effectiveness of the cooling system.

Higher Viscosity

Can You Use Mineral Oil in a Water Cooling Loop

Mineral oil is thicker and more viscous than water, with a dynamic viscosity of around 20-30 centipoises (cP) at room temperature, compared to the viscosity of water at around 1 cP. This higher viscosity means the pump in the cooling loop will need to work harder to push the mineral oil through the various components, such as the CPU block, GPU block, and radiators. This increased pump workload can lead to reduced pump lifespan and increased energy consumption, as the pump will need to operate at a higher speed to maintain the necessary flow rate.

Lower Thermal Conductivity

Mineral oil is not as good a conductor of heat as water, with a thermal conductivity of around 0.12-0.15 W/m·K, compared to water’s thermal conductivity of 0.6 W/m·K. This means that mineral oil will not transfer heat as efficiently, which can result in higher operating temperatures for the components being cooled, potentially leading to reduced system performance and stability.

Flammability and Odor

Mineral oil is a flammable liquid, which can pose a fire hazard if not handled properly. Additionally, mineral oil has a strong, unpleasant odor that some users may find undesirable, especially in a closed computer case.

Corrosiveness

Mineral oil can be corrosive due to its high sulfur content, which can potentially damage electronic components and reduce their lifespan. This is a significant concern, as the corrosive nature of mineral oil can lead to the degradation of the cooling system’s components, such as the CPU and GPU blocks, as well as the tubing and other metal parts.

Recommended Alternative: Dielectric Coolant

Instead of using mineral oil, it is recommended to use a proprietary dielectric coolant specifically engineered for immersion liquid cooling, such as ElectroCool by Engineered Fluids. These dielectric coolants are designed to be safer, perform better, and have a lower environmental impact compared to mineral oil. They typically have a higher heat capacity, better thermal conductivity, and are non-flammable, making them a more suitable choice for water cooling loops.

In conclusion, while the use of mineral oil in a water cooling loop may seem like an interesting idea, it is not recommended due to the technical drawbacks and potential safety concerns. The lower heat capacity, higher viscosity, poor thermal conductivity, flammability, and corrosiveness of mineral oil can all negatively impact the performance and longevity of the cooling system. It is best to use a proprietary dielectric coolant specifically designed for immersion liquid cooling to ensure optimal cooling performance, safety, and reliability.