Practical Guide for Miner Cooling

In scorching summer, not only the people but also the miners will have to endure the high temperature. We have shared the article Practical Guide for Mining Noise Control in the past to provide many practical means for the mining workers to get away from noise. Now, we’d like to discuss how to make the miners safely spend the scorching summer.

Where does the high temperature come from?

Why do the ASIC miners have higher hashrate than GPU miners? Because the former adopts the professional ASIC chips which will generate heat during massive calculations. That’s just the source of high temperature for miners.

Take Antminer S9 as an example. If the indoor temperature is 29℃ with cooling fans in auto mode, the air inlet temperature is about 32.℃ and the air outlet temperature is about 44.9℃. The chip temperature on mining status page is about 63℃ and the chassis is about 36℃.

In the summer, the temperature in most places will be more than 35℃ or even 40℃, which is very “fatal” for miners because they’re also generating heat. The high temperature will damage the chip to reduce the hashrate and shorten the service life of miners. Therefore, it is very necessary to conduct effective cooling in summer.

Cooling Methods Prohibited by Engineers

If the miner noise is only disturbing the people, the consequences of high temperature will bring more serious results, which will not only shorten the service life of miners, but also affect the physical and mental health of the mining workers.

Therefore, many mining workers have come up with various cooling methods.

Worker A: Put the miners in air-conditioned room with 24-hour cooling mode.

Response from Engineer: Some mining workers choose to conduct small-scale mining (within 10 miners) in non-professional mining farms such as home, garage and loft. If there are only several miners, the air conditioner can bring satisfactory cooling effect. However, if there are many miners, the cooling effect of air conditioning will be not so satisfactory. Secondly, even an ordinary household air conditioner will consume about 1.3 kWh per hour, that is, about 31.2 kWh per day, while the Antminer S9 only consumes about 35 kWh per day. So, it’s uneconomical in terms of costs.

Worker B: Open all the windows and doors, and even the ceiling if possible.

Response from Engineer: Although it’s the correct idea to promote ventilation, the issue of dust proof should be attached great importance. If the miners are in open environment, when the cooling fans blow the wind into the chassis, some dust, insects and debris are most likely to penetrate inside to damage the precision components such as the hashboard and affect the miner performance. If the dust has not been cleaned up in time, the operating temperature will keep rising and eventually damage the miners.

Worker C: I intend to install two fans of higher speed for my miner.

Response from Engineer: Theoretically, high-speed fans can be installed to replace the low-speed fans, but why do Antminer adopt the cooling fans of different models and speeds? That’s because the configuration of Antminer has been repeatedly tested by engineers and each component will be taken into consideration to achieve the best overall operation. If the original fans are replaced by high-speed fans arbitrarily, it means higher power consumption and noise and the overall performance of the miner will also be affected.

How to cool the miner in a scientific way?

We visited the Antminer technicist in the past and they put forward some suggestions on the cooling methods. Let’s have a review first (please refer to Professional Miner Maintenance suggestions from Antminer technicist):

Antminer must adopt the original brand of cooling fans since the quality of other brands cannot be guaranteed.
High-speed fans cannot be replaced by low-speed fans, however the low-speed fans can be replaced by the high-speed ones.
Regular dust removal is very important. Do not dismantle the miner. Use high-pressure blower to blow the dust backwards at the interval of one month.
Monitor the miner temperature all the time. Pause if some problems occur. The temperature difference of hashboard should be within 10℃.
It is not recommended to dispose the Antminer in oil for heat dissipation.
The most proper indoor temperature for miner operation is 20-30℃.
The chip temperature should be controlled at about 70-80℃, overheating may result from the dust accumulation.
As for the issue of low chip temperature, if the miner operation is normal, the fan will run at low speed with less power consumption.

Then, how can we conduct heat dissipation scientifically? Let’s have a look at the way of heat transfer.

The heat transfer can be concluded as the following three ways: heat conduction, heat convection and heat radiation.

Heat conduction refers to the temperature difference inside the object or the direct contact of two different objects without relative motion. The heat is transferred only by the thermal motion of the internal particles. For instance, people often feel cold when holding ice cubes.
Heat convection refers to the process of heat transfer caused by relative displacement of different parts of the fluid (gas, liquid or some solid such as powder). For instance, add cold water into boiling water to make the warm water.
Heat radiation refers to a process during which the objects without touching each other transfer energy through electromagnetic waves. The internal energy of the object is converted into energy of electromagnetic waves (usually in the form of infrared rays). For instance, the heat from the sun.

Therefore, there are three quick cooling methods as follows:

Ⅰ. Direct contact with the objects of lower temperature

At present, the water cooling and oil cooling systems have been tested. It’s a way to achieve a cooling effect by directly contacting the miner with coolant. Apart from reducing temperature, there is no noise generated by the fans. Although it has not been widely used and popularized at present, this method will most probably be used to replace cooling fans with the development of technology.

Ⅱ. Put miner in the place of good ventilation and low ambient temperature

As mentioned above, it’s necessary to ensure good ventilation and dust prevention. Nowadays, professional mining farms will be installed with window screens and louvers to reduce dust and prevent air return. Moreover, many large mining farms will be installed with industrial negative pressure fans with very good heat dissipation effect.

The mountains and rivers are usually the places with lower temperature. The higher altitude, the lower temperature. In addition, the places of high latitudes have relatively lower temperatures throughout the year, which are relatively more suitable for mining.

Ⅲ. Reduce heat from the sources

It’s impossible to shut the miners down, but cleaning is quite necessary. Regular dust cleaning can effectively prevent the problem of overheating. The specific methods include using high-pressure gun to blow from the air outlet to the inlet for several times.

Creative cooling methods by EastShore customers

In addition, the EastShore customers have also come up with a lot of creative cooling methods as follows (Tips: Not verified, be cautious to follow).

A: Spend 80,000 yuan to dig eight 100-meter wells installed with heat exchange bars inside and blow the cool air into the closed room. It’s enough to support 300 miners to run at low temperature all year round. The biggest advantage is the one-time investment, only the electricity fees of the fans need to be paid without other maintenance costs. Moreover, there’s almost no dust. Even if the outdoor temperature is nearly 40°C, the indoor temperature can still be maintained at around 28°C.

B: To cool the air inlet with water curtain and install negative pressure fan at air outlet to realize heat insulation, so that the miner temperature will not exceed 70℃.

C: As for the miner cooling, some experienced workers usually refuse water curtain, so it’s better to cool down by natural wind.

Heat insulation is undoubtedly necessary;
Check the wind direction to enable cold wind to blow into the miner from the air inlet direction;
According to aerodynamics, it’s better to design the air inlet as a bell mouth to produce certain amount of air compression when air enters. Just Google “compress air to reduce temperature” for details. It’s the same principle as that in the refrigerator;
It’s necessary to install negative pressure fan at the air outlet.

D: Spend 10 yuan buying one ice cube and place inside the mining farm. One ice cube is just durable for a whole day.

E: Take the frozen bottled water out of the refrigerator and place them at 10cm away from the miners. Then use ordinary electric fan to blow the cold air for the inlet for heat dissipation. Tips: Place a plate below to collect the dews on the bottles.

Do you have any other good cooling methods? Please share your attempts in the message box below.

Appendix

Series articles on crypto miner maintenance: