We summarize the following scenarios in which you may find the fans are having issues.
Scenario No.1——the fan speed is too low

Scenario No.2——the fan speed exceeds 7000

Scenario No.3——the kernel log shows the fan is lost or the speed is too low
Check the kernel log and if you see the line: Fatal Error: some Fan lost or Fan speed low!,

Scenario No.4——fans are missing in the miner status
There should be two fans display in the miner status but you find only one.

Scenario No.5——more than a normal amount of fans are detected
There should be two fans display in the miner status but you find three or more fans.
If you encounter any one of the above scenarios, please follow the troubleshooting steps as below,
Please test the miner with a known good working control board.
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