A Practical Guide to Cooling for Miners

In the hot summer, the people and the miners have to endure the high temperature. So here, let’s talk about letting the miners spend the hot summer safely?

Where does the high temperature come from?

Why is the hash rate of ASIC miners higher than GPU miners? Because the former uses professional ASIC chips, heat will be generated during many calculations. This is just the source of the miners' high temperature.

Take the Antminer S9 as an example. If the indoor temperature is 29°C and the automatic mode has a cooling fan, the inlet air temperature is about 32°C, and the outlet air temperature is about 44.9°C. The chip temperature on the mining status page is about 63°C, and that of the chassis is about 36°C.

In summer, the temperature in most places will exceed 35°C or even 40°C, which is very "fatal" for miners because they are also generating heat. The high temperature will damage the chip, reduce the hash rate, and shorten the miner's life. Therefore, effective cooling in summer is essential.

Cooling methods prohibited by engineers

Suppose the noise of the miners only disturbs the people. In that case, the consequences of high temperature will bring more severe consequences, which will shorten the life of the miners and affect the physical and mental health of the miners.

Therefore, many miners have come up with various cooling methods.

Miner's method: Put the miner in an air-conditioned room and keep it cool for 24 hours.

Recommendation: Some miners choose to conduct small-scale mining (within ten miners) in non-professional mining farms such as homes, garages, and attics. The air conditioner can bring an excellent cooling effect if only a few miners are. But if there are many miners, the cooling effect of the air conditioner will not be so satisfactory. Secondly, even an ordinary household air conditioner consumes about 1.3 kWh of electricity per hour, or about 31.2 kWh per day, while the Antminer S9 only consumes about 35 kWh per day. Therefore, it is not economical in terms of cost.

Miner's method: Open all doors and windows, and even the ceiling if possible.

Suggestion: Although advocating ventilation is the correct way of thinking, the issue of dust prevention still needs to be taken seriously. Suppose the miner is in an open-air environment when the cooling fan blows the wind into the chassis. In that case, some dust, insects, and debris are most likely to enter the interior, damaging the precision parts such as the hash board and affecting the miner's performance. If the dust is not cleaned up in time, the working temperature will rise, eventually damaging the miners.

Miner method: I plan to install two higher-speed fans for my miner.

Suggestion: In theory, high-speed fans can be installed instead of low-speed fans, but why do Antminers use different models and speeds of cooling fans? This is because engineers have repeatedly tested the configuration of the Antminer, and each component will be considered to achieve the best overall operation. If the original fan is replaced with a high-speed fan at will, it means higher power consumption and noise and will also affect the miner's overall performance.

How to scientifically cool down miners?

Antminer recommends using original brand cooling fans.

High-speed fans cannot be replaced with low-speed fans, but low-speed fans can be replaced with high-speed fans.

Regular dust removal is essential. Do not disassemble the miner. Instead, blow the dust backward with the dust removal fan every other month.

Monitor the miner's temperature at any time. If something goes wrong, please pause. The temperature difference of the hash board should be within 10°C.

The most suitable indoor temperature for miners is 20-30°C.

The temperature of the chip should be controlled at about 70-80°C. Dust accumulation may cause overheating.

As for the low temperature of the chip, if the miner is running normally, the fan will run at a low speed, and the power consumption will be lower.

So, how to dissipate heat scientifically? Let's take a look at the way of heat transfer.

Heat transfer can be summarized into three ways: heat conduction, heat convection, and heat radiation.

Heat conduction refers to the temperature difference within an object or direct contact between two objects without relative movement. The heat is only transferred by the thermal movement of the internal particles. For example, people often feel cold when holding ice cubes.

Thermal convection refers to the heat transfer process caused by the relative displacement of different fluid parts (gas, liquid, or certain solids such as powder). For example, add cold water to boiling water to make warm water.

Thermal radiation refers to how objects transfer energy through electromagnetic waves without touching each other. The object's internal energy is converted into electromagnetic wave energy (usually in the form of infrared rays), for example, heat from the sun.

Therefore, there are three rapid cooling methods as follows:

1. Direct contact with objects with lower temperature

The water cooling and oil cooling systems have been tested. This method achieves the cooling effect by directly contacting the miner with the coolant. In addition to lowering the temperature, the fan does not produce noise. Although it has not been widely used and popularized, this method is very likely to be used to replace the cooling fan with the development of technology.

2. Place the miner in a place with good ventilation and low ambient temperature

As mentioned above, good ventilation and dust protection must be ensured. Professional mining farms will install window screens and shutters to reduce dust and prevent air backflow. Moreover, many large-scale mining farms will install industrial negative pressure fans, and the heat dissipation effect is good.

Mountains and rivers are usually places with lower temperatures. The higher the altitude, the lower the temperature. In addition, high-latitude areas have relatively low annual temperatures, which are relatively more suitable for mining.

3. Reduce heat from the source

It is impossible to shut down the miners, but cleaning is essential. Regular dust removal can effectively prevent overheating problems. The specific method includes blowing the dust removal fan to the air inlet several times from the air outlet.

Client's creative cooling method

In addition, some customers have come up with many creative heat dissipation methods, which I will share with you.

A: Dig eight 100-meter wells, install heat exchange rods in them, and blow air-conditioning into the enclosed room. Enough to support 300 miners operating at a low temperature all year round. The most significant advantage is that it is a one-time investment and only needs to pay for the electricity bill of the wind turbine, without other maintenance costs. Moreover, there is almost no dust. Even if the outdoor temperature is close to 40°C, the indoor temperature can still be maintained at about 28°C.

B: The air inlet is cooled by a water curtain, and the air outlet is insulated with a negative pressure fan so that the miner's temperature does not exceed 70°C.

C: For the cooling of miners, some experienced workers usually reject the water curtain, so it is best to use natural wind for cooling.

Check the wind direction and let the cold wind blow into the miners from the direction of the air inlet;

According to aerodynamics, the air inlet is best designed as a bell mouth, which produces a certain amount of air compression when the air enters. The principle is the same as that of a refrigerator;

We need to install a negative pressure fan at the air outlet.

D: Buy some ice cubes and put them in the mining farm. An ice cube can only last a whole day.

E: Take out the frozen bottled water from the refrigerator and place it 10cm away from the miner. Then use an ordinary electric fan to blow cold air into the air inlet to dissipate heat. Tip: Put a plate underneath to collect the dew on the bottle.