ASIC Miner Maintenance: Cleaning, Fans, Thermal Paste and Environment
Above all, an ASIC miner needs clean, cool air. In practice, it is enough to blow out the dust regularly, keep an eye on temperatures and fan speeds, and replace a faulty fan straight away. When one hashboard is consistently warmer than the others, it is time to have the thermal paste checked by a service centre.
Summary
- Monitor temperatures, fan speeds and hashrate automatically – set up alerts.
- Blow out dust with dry compressed air, always with the machine switched off.
- Replace fans with the same type – a weaker fan means overheating.
- Leave re-pasting the hashboards to a service centre; when heatsinks are removed, chips can be torn off.
- A good environment helps most: intake separated from exhaust, no condensation, a stable power supply.
What you will need
- A compressor with a water separator, or compressed air in a can.
- A soft anti-static brush.
- A Phillips screwdriver.
- Spare fans of the same type – the same size, voltage and connector as the originals.
- A respirator and gloves – dust from a miner is fine and dirty.
How often to do what
| Task | When | Why |
|---|---|---|
| Checking temperatures, fan speeds and hashrate | continuously, automatically | you spot a problem before the machine shuts down |
| Blowing out dust | regularly, more often in dusty environments; always when temperatures rise for no reason | dust insulates the heatsinks and slows the fans |
| Checking the fans | at every cleaning | a noisy bearing is the first sign of the end |
| Checking power cables and connectors | at every cleaning | a hot or discoloured connector risks melting |
| Thermal paste on the hashboards | when one board is consistently warmer | dried-out paste impairs heat transfer from the chips |
| Firmware update | when a new version fixes your problem | on one machine first, then on the others |
Step 1: Note down the baseline values
- Open the miner's web interface.
- Note the hashrate of each hashboard, the board and chip temperatures and the fan speeds.
- After cleaning, you can then easily compare whether anything has improved.
Step 2: Clean the dust out of the miner
- Switch the miner off and unplug it. Wait a few minutes for the fans to stop and the power supply to discharge.
- Take the machine out of the room where your other equipment is – the dust will fly everywhere.
- Hold the fans with a finger or the brush so that they do not spin up while you blow. Overspinning destroys the bearings.
- Blow against the airflow: from the exhaust towards the intake. The dust then leaves the same way it came in.
- Blow out the power supply only through its grilles. Do not open it – the capacitors can hold a high voltage.
- Check the hashboard connectors and power cables. Discoloured plastic or a burnt smell means the cable must be replaced.
Do not use a vacuum cleaner – it does a poor job of getting dust out of heatsinks and can create static electricity.
Step 3: Check and replace the fans
- Compare the speeds of all fans in the interface. A fan that is significantly slower than the others or has a noisy bearing needs replacing.
- Disconnect the power, undo the fan screws and pull out its connector.
- Turn the new fan so that the arrow on the frame points the same way as on the others.
- Use the same type. A weaker or "quiet" fan cannot remove enough heat, and the firmware may report a fan speed error.
If you want to make the miner quieter, a soundproof box is better than weaker fans – see How to quieten an ASIC at home.
Step 4: Thermal paste and hashboard heatsinks
The chips on the hashboards transfer heat to the heatsinks through thermal paste or gel. Over time it dries out and the board runs hotter than the others. Re-pasting means taking the board apart and removing the heatsinks, during which a chip can easily be torn off. We therefore recommend leaving this work to an ASIC miner service centre. How to read board temperatures is explained in the article ASIC temperature sensors.
Step 5: Adjust the environment
| Parameter | Recommendation |
|---|---|
| Intake air temperature | Bitmain allows 0–45 °C for the S21; for a long service life, stay around 20–25 °C. |
| Humidity | 10–90% without condensation. Let a machine brought in from the frost warm up to room temperature before switching it on. |
| Airflow | Separate intake and exhaust so that hot air does not return into the machine. |
| Dust | Put a filter on the intake and clean it. Do not run the miner in a workshop, an unfiltered barn or next to a road. |
| Power supply | A dedicated, correctly rated circuit. You will find the procedure in the guide How to connect an ASIC miner. |
| Altitude | Above 900 m above sea level, reduce the maximum ambient temperature by 1 °C for every 300 m. |
On a larger farm or in a cellar with several machines, deal with heat removal as a whole – see Mining farm cooling.
Common problems and solutions
| Problem | What to do |
|---|---|
| Temperatures are high even after cleaning | Check the room temperature and whether exhaust air is being drawn back in. If only one board is hot, it is most likely the paste or the heatsink. |
| Fan error after replacement | Check the connector and fan type. The firmware requires a certain speed range. |
| The hashrate of one board gradually drops | A typical sign of faulty chips or overheating – see ASIC miner faults. |
| Hot power connector | Switch off the machine and replace the cable as well as the socket or PDU. Do not use splitters or extension leads. |
What next
If you do not want to deal with maintenance, keep your miner in our ASIC miner hosting – installation, monitoring and servicing are handled there by data centre technicians. If something does not work, we will repair the miner at our service centre in Prague.
Sources
Frequently asked questions
How often should an ASIC miner be cleaned?
Can I clean an ASIC miner with a vacuum cleaner?
Can I fit quieter fans in a miner?
Do I have to update the firmware?
When should the thermal paste on the hash boards be replaced?
This text was prepared with the help of AI. Facts, figures and procedures were checked by Yegor.
