I have a RasPi 3B with an aftermarket case with fan running my ADS-B setup. It also has heat sinks on the CPU, GPU, and RAM. With the fan installed, the average CPU temp was around 40°C. Unfortunately, the cheap case fan soon began making an awful racket so I removed it. Ever since then my CPU temp has been averaging around 50°C. In the graphs below, you can clearly see when the fan was removed.
Are those temps considered acceptable for decent longevity of the Pi hardware?
I think they are acceptable. My feeder is a Pi 3B in a black case with a small heatsink stuck to the CPU which has been feeding continuously since Nov 2017. It’s temperature in all that time has been around 50-60C normally and higher than that during the summer, since it’s in a south-facing window. Here’s the same graph since I installed the packages.
I bought it in Mar 2017 and it was in general use above 60C for around 8 months until it became a feeder, so it’s been like this pretty much continuously for almost 3 years. I’ve not seen any signs that this temperature has been detrimental to it.
Thanks for the feedback! That was exactly the kind of info I was looking for.
I’m glad to know that these little computers can run for years at those temps. 
No probs, I think you’ll be okay with the 3B (or 3B+) at that temp. Note that the 4B does seem to be a different story though and is more sensitive to temp, causing it to throttle back a bit more readily than might be desired.
It had updated temp management in a Raspbian update a while back, which improved things a lot, and there are videos around, like this and this from EC, exploring cooling solutions.
For reference it’d be interesting to see temp graphs from anyone running the 4B as a feeder with a comment on what cooling, if any, it has.
A Pi4 throttled back is probably still faster than a Pi3 though.
If you can tell me how to generate the graphs I’ll share my 4 data with you! Doing spot checks it seems to run at a cool 30C generally with heat sinks and a 3v fan in a decent case available from Amazon. I had heard the standard case was a bit of a sweat box. Mine moved to loft so it’s getting lots of cooling now but I plan to monitor carefully in summer when I expect to see temperature rise. (It was 30 sat in main house but maybe that explains why my wife always complains the heating isn’t on high enough 
). I used to work with semiconductors years ago, sure running hot will reduce longevity but that doesn’t look that hot. The biggest threat is thermal stress from changing temperature (back then some people left their PCs running cintinuously because they thought start stop stress of turning on and off reduced lifetime) yours looks fine. Being on a window ledge is more a threat because of changing stress I’d say and that one did ok.
Nice one, thanks! You can use the excellent graphs installer with UI mods by @wiedehopf to get them on and running. Then you just go to
http://your_piaware_ip/graphs1090
in your browser to see the graphs.
Agreed, especially south-facing. I have a piece of white card as a sun shield. I think it’s going to be going up into the loft like yours quite soon, once I can work out how to power it! Pic below (older from when it was attached to the mini mag mount but same main setup).
Oooo I like the pre amp! I was lucky to have wired in a socket years ago to loft, spur off loft light, so power wasnt a problem. Position was though, but a long ‘powered’ usb extension lead allowed short coax run from aerial to dongle both remote from pi. But then how to power that preamp? What voltage is that?
There’s a hole in the corner of the ceiling where a telephone extension used to go into the loft in order to route its way ultimately downstairs. I think that hole has just become a 5A mains supply conduit!
The 1090Mhz filtered preamp is this one by Uputronics. This one is the SAW filter model, they have a more expensive ceramic filter model. It can be powered either by mini-USB or by bias tee through the coax. In that pic it’s being powered with a 0.5m USB lead from one of the Pi’s USB sockets. It works really well and I’m pleased with it.
The CPU temp is pretty meaningless without knowing the ambient temp.
Quoting the CPU temp as say 10°C above ambient shows all is well.
Good point for looking at load/cooling issues: in addition to absolute temp.
Does anybody track processor load? Pi4 should find job more trivial and not be so stressed. Or not?
Although if it’s 130C and ambient is 120C then you’ve got a whole other problem that the fire brigade will need to deal with
“There’s a hole in the corner of the ceiling where a telephone extension used to go” - are you sure about that? You didn’t just make the hole and then convince yourself that it used to be there before
I’ll give you guys a fit now, this is the top corner of my shack ceiling up to the loft. It’s a bit dusty because it’s right in the corner, above all my shelving and is practically impossible to get to from down here.
You can see it started as one hole which got ahem extended over the years!
I think you are fine - mine range from as low as 30 to as high as 85 in the summer sustained without problem or any degradation in signal/performance that I can see so far.
Haha, love it, that sounds like a well-rehearsed Wife-Friendly[TM] take on the situation!
It’s my radio shack and like Yorkie bars, it’s not for girls 
I am operating my RPi 3 since July 2919 in a passive case without fan. Only the default heatsinks are mounted.
It’s indoor all the time, in sumer season with environmental temperature of up to 32°C
The SoC temperature never went over 60°C and the device is still running fine.
It’s not only used for ADS-B feeding, it also hosts a VirtualRadar Server instance which combines my two receivers into one interface. This causes an additional CPU load of 10-15% and it works without issues.
For a shack, that actually looks pretty sophisticated, I’d expect a more “unfinished wood” look.
