Project: External Cooling

[Dirk Diggler]

Small update, I'm continuing to monitor temperatures as I need to know how things work in reality before investing time in design and construction. My PC will idle for another two weeks as I'm at work for the next fortnight, so it's a good time to collate data. Idle temperatures are most interesting in winter because that's where all the risk is (freezing fluid). My wife has informed me that there's been frost the last few days and as you can see my fluid temperature has remained around 20C which is much higher than I would have expected.

Great for winter, but definitely not good for summer. I need to ensure my final build is versatile and able to adapt automatically to the external influences.

Click on image to enlarge.

 

[Dirk Diggler]

It looks like I'll have to modify my plans based on the testing to date. The temperature has plummeted to -7°C and this has meant my external enclosure temperature has lowered to around 6°C. I won't know until I get home whether the anti-con heater has been called into action (I've got a power meter on it) but I've got a sneaky feeling that it has as it's set to kick in at 5°C.

What's interesting is the fluid temperature, it's still hovering around 20°C. That's pretty much mission accomplished right there as it proves that even with external sub zero temperatures, the enclosure is keeping itself above 5°C and amazingly the fluid temperature is staying at room temperature - so no chance of freezing.

The only way fluid can be so much warmer than the enclosure it's in has got to be down to the internal radiator in the case pulling the warm air from the office through into the case. It's not only keeping the fluid warm but it's also keeping the components in the case cool.

I need to cancel my plans to move all my cooling gear to the external enclosure, it's just not going to work when temperatures are sub-zero. So, this system has been idle for 4 weeks which has been a great test in terms of freezing fluid risk, however it's now time to pound some gaming and see how that's working out in these freezing conditions.

Here's a graphic of what's been discussed in this post.

 

[opstrat]

hy, read your post in the fish thread. yes there is obviously submersible heaters. its being kept outside that is the problem generally they don't like the ends of them getting wet and obviously the power leads. there are heaters known as titanium heaters that have no thermostats and are fully submersible but are controlled externally on a thermostat/controller. have you thought a bout putting anti freeze into the water?

im not 100% sure on what your up to. i see that its in a garage so a heater getting rained on isnt an issue. i am over in the moodiesburn/cumbernauld area and have a 50 watt heater spare that will be more than enough i would imagine. if you want i can get that to you and see if it works for you.

 

[Dirk Diggler]

Yes, I've got additive in there.

I've ordered an Inkbird ITC-306UK and the plan would be to have the heater plugged into one socket and the radiator fans plugged into the other socket. Radiator fans would kick in at 25C and heater would kick in at 15C. I
would expect the water to be 20C or higher 90% of the time so the heater is essentially a fail safe for really cold weather.

I would need to set this up with a little tank with a couple of litres of water in it, so I'm thinking even a low wattage heater would do? What would you recommend if someone was asking for a quality heater for a small tank?

 

[opstrat]

something like this is small enough for what your needing to do.

https://www.completeaquatics.co.uk/...ies/aquarium-heaters/interpet-nano-10w-heater

as its only a couple of litres it will take no time at all to keep the water from freezing

 

[Dirk Diggler]

@opstrat thanks for the link. 10w is really good as it'll be economical to run. I'm pretty sure I can set this up so that the water is maintained above 15C but I just need this fail safe in place. I've got a space heater in there just now, but it's creating complications when it comes to efficient cooling.

Anyway, thanks again. I'll pick one of those up and have a think about how to include a container with a few litres of water to house it.

 

[WJA96]

I'm not sure where you live, but in Lanarkshire it isn't unusual to have temperatures as low as -25°C in winter.

I think you mean -2.5C in winter. While there are parts of the highlands that get VERY cold, Scotland in general is warmer than it should be because of the Gulf Stream. They grow Palm Trees in Ayrshire all-year round! Lanarkshire is in the central lowlands of Scotland and is actually quite warm all year round. In my lifetime (52 years)the temperature in Scotland has never dropped under -22C and I believe the coldest temperature ever recorded (Braemar) was about -23C, in 1963. In the whole of 2017 it didn’t drop under -4C, So I think preparing yourself for -25C might be a bit extreme.

 

[Dirk Diggler]

@WJA96 I've lived in Lanarkshire all my life and can assure you it isn't warm. However, the -25C I should have described as "not unheard of" as opposed to "not unusual".

Anyway, it's a moot point. My plans have been classic over engineering. The Mercury has hit -5 this winter and my fluid stays above 20C. It's just not going to freeze due to the amount of time the fluid spends in the office side of the loop which is always around 25C. I leave the external fans at 200rpm and the fluid is 20C+ no matter what the garage temperature is. As soon as the GPU goes under load the external fans ramp up to 2000rpm.

The result is a GPU temperature of 20C on idle and 27C under full load. It's well and truly mission accomplished.

 

[Distracted]

Is this still going @String

 

[dingleweed]

He's been found lying unconscious with a three quarter filled glass of antifreeze in a pool of half munched Doritos after his post to Engineering Anonymous was ignored.

It's quite a nice silvery box.

 

[Distracted]

I'm imagining a crusty orange joker-esque dorito smile on the face of some strangers corpse now. Oh and the glass is a martini glass for some odd reason and @String is in a tux. Beside an actual swimming pool.

It's still not the strangest thing I've thought about today.

 

[Dirk Diggler]

Is this still going @String

I got it finished.

https://forums.overclockers.co.uk/threads/itx-custom-loop.18817860/

 

[Distracted]

Very nice. Thanks

 

[loonyk]

uhm...at least could have inserted the pvc pipe in a block holes and then hose....but aint that baaaad