75

Is it possible to reliably run a Pi in an airtight (watertight) case or is some form of ventilation required for cooling? I'm assuming it doesn't chuck out too much heat, but am wondering whether running it indefinitely this way may cause issues.

Alex Chamberlain
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berry120
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    This is a bit of a teaser - what use for an RPi needs a watertight case? – Jon Egerton Jun 24 '12 at 23:10
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    @JonEgerton As the brains for an off road robot or even a boat / submarine? – berry120 Jun 25 '12 at 00:17
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    Anything left outdoors like a weather station or spy^Wnature cam server. – XTL Aug 24 '12 at 06:54
  • @berry120 Are you making the proposed case on your own, or buying? – FCTW Dec 20 '12 at 23:47
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    Just thought I should note that the question doesn't actually give much information about what is desired. For instance, an airtight aluminum case floating in the Arctic Ocean is different from a polystyrene airtight case in your attic. A case can be airtight, but heat still has to escape. – Tai Viinikka Jul 03 '13 at 01:09
  • Did anyone noticed any (airtight) case with thermal conductor on hottest IC, i.e. ethernet controller and ARM? I have in mind a low-profile case with copper conductor leaning on hot ICs, which then passively dissipate heat on outer case surface...? – TomiL Oct 17 '13 at 13:06
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    @TomiL problem with such copper case would be that it can work also opposite way - for example on direct sun. – Marki555 Dec 28 '14 at 00:51

4 Answers4

71

There are no ventilation or cooling requirements.

This has been verified by an RPi admin here.

tlhIngan
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Jivings
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44

Yes, under usual circumstances it should be possible to run the Raspberry Pi in an airtight case. I have measured some temperatures confirming that there is amply thermal headroom.

For reference:

  • 22°C room temperature
  • 42°C idle

I ran sysbench to stress the CPU:

sysbench --test=cpu --cpu-max-prime=20000 run
  • 45°C 20 s
  • 46°C 2 m
  • 47°C 5 m
  • 48°C 12 m

Since the temperature did not seem to raise any further, I put a paper hood over the CPU to simulate the "airtight case scenario".

  • 49°C 20 s
  • 50°C 2 m

After another half an hour there was no further increase of the temperature.

Bengt
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9

Based on my test Raspberry Pi runs relatively cool even when the CPU is 100% loaded for longer periods, so I think there shouldn't be a problem (I did not try loading the GPU though).

2

According to this test the USB 3.0 controller on Raspberry Pi 4 cannot work at full speed if there is no fan. The slow down without a fan could be 2-3 times. In the test the maximum speed was 346 MB/s for USB 3.0 (for comparison, it was 44 MB/s for an SD card). So depending on your speed requirements and how often you need it, you may or may not need active cooling.

keiv.fly
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