Bitcoin ASIC mining machines produce a lot of heat; cooling is necessary to maximize performance and prolong the lifespan of ASIC miners. Cooling is the easiest way to improve performance. You can achieve cooling with an immersion cooling liquid system or immersion cooling mining rig. In this article, you'll learn how the immersion cooling system works, its advantages, and how you can set it up for your mining data center.
What is Immersion Cooling?
Immersion cooling, or liquid submersion as it is also called, is the use of dielectric coolants to achieve a cooling effect in electronic parts such as computer processors, TVs, etc. Dielectric coolants are thermally conductive (transfer heat) but do not conduct electricity. An immersion cooling PC has its components, or full servers, immersed in dielectric coolants and is thus able to cool faster and more efficiently without conducting electricity. This type of mining cooling systems is regularly used for cooling large transformers in electrical systems. But more IT hardware manufacturers are deploying the technology to cool data centers globally. Immersion cooling is more effective than traditional cooling fans because heat is exchanged between the warm coolant and cool water circuit using radiators. High-density supercomputers, such as the Cray-2 and Cray T90, use large liquid-to-chilled heat exchangers for heat removal. Dielectric coolants are preferred because they do not interrupt or interfere with the electrical flow in circuits and even provide some level of insulation for components.
What is the Difference Between Immersion Cooling and Water Cooling?
Water cooling works by running water through small pipes to conduct heat and then running the pipe in front of fans to remove heat and re-cool the water. Water is 30 times more thermally conductive than air, so water-cooling systems quickly replaced air-cooling systems. But because water is corrosive to components and a poor conductor of electricity, cooling water must be enclosed within pipes. But immersion cooling, on the other hand, uses non-electrical thermal conductive liquid in which the components or entire servers are immersed. This causes the heat to be transferred directly from the source (the components) to the working fluid. This is more effective than water cooling systems that incorporate fans and cooling pipes. Direct heat transfer ensures even and complete heat removal at a rate that copes with the amount of heat produced by computers.
The requirements for cooling fluids (thermal-conducting, non-electric conducting) limits the options to four types:
- Deionized water
- Mineral oils
- Fluorocarbon-based fluids
- Synthetic liquid
The use of dielectric liquids significantly increased the costs of setting up immersion cooling systems, but with innovation, the costs are gradually reducing based on different applications. For example, some people use transformer oils which work just as fine. Other general-purpose and non-purpose oils, such as cooking, motor, and silicone, are used mostly for small mining rigs and personal computers. PC immersion cooling is efficient for PCs, GPUs, and high-powered computers such as ASICs.
Main Types of Immersion Cooling
Two main types of immersion cooling are single-phase and two-phase.
- Single-Phase Immersion Cooling
What is immersion cooling single-phase? In single-phase immersion cooling, the coolant is kept in a constant physical state so that the temperature never changes. The single-phase coolant never freezes or boils. This is achieved by pumping the coolant through a heat exchanger, which transfers heat to a cooling circuit. The cooling circuit is usually water-based. Single-phase immersion cooling allows the dual use of water circuits and immersion coolants in an open-bath system. The coolant never comes in contact with the water as the heat exchanger separates them, keeping the open bath system effective. This is important to prevent the coolant from evaporating.
- Two-Phase Immersion Cooling
What is two-phase liquid immersion cooling? The two-phase immersion cooling system uses a working fluid in both a liquid and gas state, a cold condenser, semi-open baths, and the principle of latent heat. Latent heat is the heat or thermal energy required to change a liquid's phase, for example, from liquid to gas. The coolant remains at its boiling point and continues to absorb heat from the computer or heat source. The added heat causes the liquid to evaporate into gas, be trapped, and pass over the condenser. The condensed gas changes to a liquid and falls back into the pool. The semi-open bath allows continuous heating-condensation to remove heat via immersion cooling.
What equipment do I need to have in order to use SLIC (Single-phase, Liquid Immersion Cooling)?
You need five different equipment to set up an ASIC immersion cooling system. These equipment are:
- Dielectric Coolant: Bitcool BC-888 is probably the best dielectric coolant for ASIC systems. It is engineered to provide efficient heat removal and cooling under different conditions. ElectoCool is your best choice if you have other non-ASIC systems such as CPU and GPU.
- Immersion Tanks: the three things to consider for immersion tanks are volume (depth and height), material, and size. The most common SLIC baths can hold between 4 to 40 ASIC miners and have enough depth to ensure 2 cm of coolant covering after full immersion. The tanks should also have a minimum of 1 cm spacing around them to allow easy outflow of coolants. It is important to arrange the miners in single rows to reduce the thermal load on the tanks and ensure efficient cooling. Go for tanks made of steel, lucite, custom nylons, and stainless steel. The coolant should be pumped from the bottom and removed from the top. It is optional to use fans as they have little to no effect and will only increase electricity consumption.
- Pumps: the best pump for liquid immersion cooling is probably the centrifugal pumps with Viton seals. Check out the pump’s efficiency and output and ensure it meets the required volume.
- Piping: use chlorinated PVC (CPVC), copper, or steel pipes as they have the best resistance to coolant chemicals, do not contaminate coolants, and have an amazing lifespan.
- Heat Rejection: dry coolers work best with SLIC. Calculate the volume of heat to be removed and get a cooler that meets the workload. You can choose coolers from between 2 kW to 1,000 kW.
Advantages of Immersion Cooling for Bitcoin Miners
For good reasons, immersion cooling is probably the best ASIC miner cooling system. Here are the best advantages that immersion cooling provides:
- More effective heat dissipation and cooling: dielectric coolants are more effective thermal conductors and dense than air, so they are better at absorbing and dissipating heat from mining equipment. Immersion cooling is easily the most effective way to cool ASICs anywhere. This is a major advantage of the best mining hosting service.
- Increased hardware lifespan: heating and vibrations of working parts cause wear and tear and decrease components' lifespan. But with immersion cooling, devices and components can last a long time.
- Improved working efficiency: a liquid cooled Bitcoin miner, for example, typically works better and more efficiently than air or water-cooled miners because the cooling effect saves more electricity while doing more work. The efficiency, measured in J/TH, is greater for immersion-cooled miners, which do not need fans. The electricity saved from absent fans can then be repurposed for mining.
- Improved mining conditions: immersion cooling prevents the entry and accumulation of dust and debris, therefore, they require less maintenance and cleaning. Removing fans also eliminates noise from working parts, leading to a cleaner and better mining process.
- Improved and safer overclocking: immersion-cooled miners can achieve overclocking (increased TH/s) because of more efficient heat removal, cooling, and better operating conditions. Miners can therefore achieve more with the miners.
While immersion cooling is great, it is not always ideal for everyone. Check your mining rig’s requirements to determine whether or not you need immersion cooling. The factors discussed in this article will guide you in making the best choice for liquid cooled Bitcoin miner. Consider the advantages and the costs before setting up your rig and immersion cooler. Hiring a professional is the best way to go if you get confused. Immersion cooling is a game changer for Bitcoin miners, but only if you get it right.