Beat the heat


#1

My Pi3 setup is in my attic, hot Texas summers. Saw an anomaly message in flightaware about the high temps, it was 85ºC at one point. Not a deal breaker for the Pi3 but not great either. I had it installed in a plastic case than came with the kit and 3 heatsinks were installed. I pulled it out of the case and for the rest of the day just let the board dangle in the attic, it was down to 75ºC at it’s peak and as soon as the sun started to go down it dropped right in line with outside temps degree for degree and was under 70ºC by bed time. 70ºC by the way is the threshold for the temp anomoly message on your user page in flightaware. FYI temps in the attic were around 49ºC so we’re talking ambient plus 30º.

So I order a different case and fan and put that together, reinstalled in the attic, now running ambient plus 5º!! Honestly suprised what a big difference it made, even being back in a case. No controller for the fan, just connected to 5v and Gnd on the GPIO header. That is all. Carry on!

If you care, this is the case - http://amzn.to/2tAa7Dr

And this is the fan upgrade for that case - http://amzn.to/2uLLfs8


#2

80°C is actually the point where the CPU throttle sets in, to protect it from overheating.

It will still be able to run piaware, but I am not sure running prolonged time at this temp would do it any good long term…

Edit: Nice thread title, just a coincidence or has it something to do with living in Texas (maybe Dallas?) :laughing:

Edit2: Corrected temp where throttling starts, at 85°C it is at already at 600Mhz according to this article

http://www.zdnet.com/article/no-your-raspberry-pi-3-wont-overheat-in-everyday-use-says-its-creator/


#3

I think that 80C is where the throttle starts, 85C is the maximum operational temperature for that chip.

I saw that anomaly message here in southern VA, from my FF located in my garage, a couple times, once yesterday. Probably today too, since we have again a heat advisory expecting temps around 96F again (35.5C)…

Heat index 105F to 109F (40.5C to 42.8C) means that a functional AC is required everywhere - in houses, cars, stores… keep pets in the house. I don’t have AC in the garage.


#4

I can’t really complain, end of July and we’re just breaking hundred degree temps in DFW? That’s not so bad.


#5

Ultimately, the best option when dealing with attic heat (not all that much different here in Tennessee than in Texas) is to use a few feet of coax and get your gear on the other side of the ceiling (or wall) and in to the air conditioning. Just because something can function in an extremely hot environment doesn’t meant it should if it doesn’t have to. The other thing to consider here is the dongle - which already gets nice and warm even in an air conditioned room. A case and a fan for the Pi isn’t doing anything to cool the dongle off.

At two of the residential sites I run, I’ve got the antennas outside on the roof and could have the Pi’s and dongles installed in each of those attics…but why? Running 12ft of quad-shield RG-6/U (around 15ft at the other site) from the base of the antenna, through the attic, and popping out with a nice wall plate on the top of a shelf in a laundry room (top of a bonus room closet at the other site) doesn’t rob the dongle of enough signal to even worry about - and everything stays in the air conditioning. I never have to think about the ridiculous summer temperatures in the attics, new cases, cooling fans, etc…

Both of those Pi’s are wearing Flirc aluminum heatsink cases and have been reporting temps of anywhere from 34C-40C (depending on indoor ambient temp) consistently for over two years now.

Just something to consider. :slight_smile:

Matt


#6

Absoutely considered. But…For me, this was a fun little project with near instant results and I love looking at the stats and Skyview. I didn’t want to go down the “requirement creep” rabbit hole. Sourcing coax, adapter, finding where I’m going to get power from and drilling holes in ceilings and walls to drop coax. Not fun anymore, for me. So the different case and fan and that’s it for me. If I fry the dongle I’ll get the blue FA one next, put it right back upstairs in the attic.