How to Run a Computer in a Sub-Zero Environment?

Underdog asks: "I've seen tons of Slashdot articles on cooling hardware, but my company may be taking on the task of wiring a large sub-zero (as low as -14) warehouse with temperature sensors and the requisite network equipment and computers to read them. Our initial proposal includes at least a dozen acquisition computers, hung from the racks in the freezer. Does anyone have any experience with installing computers in extremely low temperature locations?"

Like in humid environments

[chriss]

I have no experience with low temperature settings, but would assume that the main problem would be water condensating on the warmer parts of the computer. So the question would be how to make sure that the water does not short circuit anything. Experience may be taken not only from environments with low temperatures, but also from areas with very high humidity, which might cause similar problems.

Re:Like in humid environments

[Spazmania]

Extremely low humidity is also a problem: you get static electricity which damages computers.

The target humidity is 50% RH. Same as for human beings.

I've done this a lot.

[Anonymous Coward]

Electronics likes to operate in a cold environment. Mechanical stuff doesn't like cold temperatures because the lubricants usually get gummy. I used to put remote equipment in the Canadian arctic. Even commercial grade (as opposed to mil-spec.) ICs were happy to operate at temperatures below -40 deg. F.

There are many boards available which can be passively cooled albeit at sub GHz clock rates. If I had to do it right now, I'd use Damn Small Linux on a flash drive. The guys who put computers in their cars have the situation totally cased (pun intended). Get one of the little Pico power supplies which can run off a small linear fanless power supply.

You have much more to worry about the heat in the summer than the winter cold.

Condensation shouldn't be a problem

[BobPaul]

Since cold air has a lower capacity to hold water, warming the air should decrease the relative humidity of the air, bringing you farther from the dew point and make condensation less likely. Just let everything sit in the cooler to get nice and cold before you turn anything on and I think it should be just fine.

It's just for things like water blocks with peletiers where the ambient air temp is really right and the heatsink is super cold that you have condensation issues (like a can of pop.) With the extremely cold (and thus dry) ambient air this issue goes away.

My only concern would be if the freezer was often open for long periods of time letting in warm moist air, but even then I would expect it to condence on cold surfaces like the outsides of your cases, etc, and not on places that will short out.

Re:Like in humid environments - !not

[KingArthur10]

Unless of course you have workers in the sub-zero environment. Speaking from experience (Kroger Distribution Center Freezer), patches of thin ice are very common with so many people going in and out of the room. Several people (or dozen people) breathing in a room with cause a decent amount of ice buildup on various surfaces.

Ok first look in the right place

[WillRobinson]

You looking on slashdot, you dont need a IT guy, you need a good controls guy.
This is cakewalk for them.
You will want a HMI for instance google for Wonderware.
Field sensors can be done is several ways.
PLC's with say up to 128 thermocouples, which would be in enclosures to keep out moisture (nema 4) talking to ONE
pc or mutiple (MMI) (Man Machine Interfaces) vi tcp.
If I knew your layout, I could tell you completely. But really, get a good controls or I/E guy.

Re:In addition ...

[theshowmecanuck]

I believe you are thinking too small. The OP mentioned the word warehouse. I doubt even several computers would make much of a difference in heat load. I have seen warehouse freezers the size of football fields. There is likely greater heat impact from people opening doors and gaps in insulation in an area that size than from computers. Even in a small warehouse.

Re:Like in humid environments - !not

[theshowmecanuck]

The air will have 0 humidity.

Not true. It will have low humidity, but not zero. However, if the air around the computer is heated from the computer itself, I would be surprised to see any condensation. Low humidity air being heated should be able to hold more water not less. Condensation happens from moisture in warm air coming into contact with cool or cold air. This would be the opposite of what is happening in the freezer. As someone else mentioned, different thermal expansion rates of the computer hardware is probably more of an issue than humidity.

Bottom line, shop for equipment built for the job. If you have a need for this now, it is a very, very good bet that someone has done the same or similar before. I'll guarantee that you aren't the first person to have a need to run computer equipment in low temperatures. You've heard this before, and now, once again: "Don't re-invent the wheel."

For example, in a past life, we needed a gas analyzer shed full of, well, gas analyzers (Gas Chromatography TCD/Mass Spec, associated remote computers, etc.) that would pull in and analyze gas from several process lines. It was basically an insulated hut that sat outside in what could be as low as minus 50 degree celcius temperatures (not counting the bullshit windchill people like to brag with). And yes, it had heaters in it to make sure a the inside temperature was at least around plus 5 degrees C. This is the first time we needed something like this, but yes, there were several suppliers with that kind of experience available who were able to provide bids for the work. Even though it was the first time for us, we weren't breaking new ground. :-)

Re:Condensation shouldn't be a problem

[theshowmecanuck]

I too have lived in very, very cold places before. And while what you say is true, in respect to the OP of this article, you have it backwards. You are talking about taking something that is very cold into a warm place with moist air. Of course water will condense on the cold surfaces. But this is not the conditions the OP is talking about. They are not bringing equipment in from the cold, they are taking something into the cold and keeping it in the cold... where the water content of the air is low (not necessarily a low RH). The only chance of condensation would be from someone working on the equipment and breathing on it, or warm moist air somehow coming in contact with the it. The only other way would be if you moved it into an area with warmer, moister air (and not necessarily out of the warehouse.

Re:Simple solution

[theshowmecanuck]

I made a reply to another comment that relates to this: Don't re-invent the wheel. :-) There are people who already make cold service computer (and other) equipment. Yeah, they probably just build enclosures with heaters in them, but at least they worked the bugs out already (if they didn't die from the cold :-). It is very rare to come across a situation that someone else has not already had to find a solution for and now markets it!