HDDs @ 10C, and Dropping

[eduncan911]

So how cold is too cold for HDDs (in spindown) and SSDs?

I've relocated my server with numerous drives into my crawlspace. Tonight, it's getting down to 5F (-15C) outside and logging into the server I see 2x drives at 10C, others at 13 to 16C.

* 8x 4TB drives (HGST and Seagate)
* 2x OCZ SSDs (Vertext 3)
* 1x Seagate 500GB Seagate Momentus XT (2.5" w/SSD cache)

Hard to find operating ranges; but, I did find HGST specs that said 5C to 60C operating temp.

I'm wondering if I should disable the spindown during the winter months to keep them a little warmer.

Never occurred to me before; but, I think I'll install a humidity sensor down there as well.

 

[rubylaser]

I'd be more concerned about condensation than the low temps. I would definitely get a humidity sensor in there, because I would think you would be getting condensation on all of the parts of a warm, running computer in a cold crawlspace.

 

[mstone]

I'd be more concerned about condensation than the low temps. I would definitely get a humidity sensor in there, because I would think you would be getting condensation on all of the parts of a warm, running computer in a cold crawlspace.

Huh? Where would the moisture be coming from? Condensation would generally be a problem the other way, when it warms up outside and warm moist air hits the cold parts in the computer. (That's potentially a big problem, and why general purpose computers aren't usually installed outside.) At very low humidity levels like outside in the winter, there's a different problem with static buildup from fans, etc.

The various components should have specifications for both operating ranges and storage temperatures. E.g., seagate rates their drives to 5C operating temperature. That said, multiple sources have reported significantly increased failures rates below 25 or 30C. (E.g., Minimizing Hard Disk Drive Failure and Data Loss/Environmental Control - Wikibooks, open books for an open world ) I'd personally worry a lot about whether a hard disk a few degrees above freezing would spin up again, as the lubricants almost have to be optimized for temperatures 40 degrees higher.

TL;DR: I wouldn't do this.

 

[rubylaser]

Huh? Where would the moisture be coming from? Condensation would generally be a problem the other way, when it warms up outside and warm moist air hits the cold parts in the computer. (That's potentially a big problem, and why general purpose computers aren't usually installed outside.) At very low humidity levels like outside in the winter, there's a different problem with static buildup from fans, etc.

The various components should have specifications for both operating ranges and storage temperatures. E.g., seagate rates their drives to 5C operating temperature. That said, multiple sources have reported significantly increased failures rates below 25 or 30C. (E.g., Minimizing Hard Disk Drive Failure and Data Loss/Environmental Control - Wikibooks, open books for an open world ) I'd personally worry a lot about whether a hard disk a few degrees above freezing would spin up again, as the lubricants almost have to be optimized for temperatures 40 degrees higher.

TL;DR: I wouldn't do this.

Condensation is possible in any area where the relative humidity is at a level that allows it. There is moisture in the air (even cold air), so when cold air hits a much warmer object like a CPU or hard drive, condensation is possible. Condensation can happen even at very low temperatures.

 

[mstone]

Condensation is possible in any area where the relative humidity is at a level that allows it. There is moisture in the air (even cold air), so when cold air hits a much warmer object like a CPU or hard drive, condensation is possible. Condensation can happen even at very low temperatures.

I think you have your understanding of condensation backward. Condensation occurs when air is cooled to its dew point. If cold air hits a warm part, it will not be cooled, won't hit its dew point, and won't condense.

 

[rubylaser]

I think you have your understanding of condensation backward. Condensation occurs when air is cooled to its dew point. If cold air hits a warm part, it will not be cooled, won't hit its dew point, and won't condense.

Sorry, you are correct, I'm thinking about condensation on the inside of windows on a cold day, but that's from the warm air being colded when it hits the colder glass. Disregard my fear of condensation, but as said above by mstone, this is still a bad idea not only from an extreme temp. perspective, but also easier access from bugs in the warmer months and other small critters in the cold months looking for warmth.

 

[HellDiverUK]

I think it'd be a terrible idea. I had significant corrosion due to dew on a Poweredge 2950, and on the drives within it, because the local guy thought running the AC at 15C all the time was better for the server.

 

[eduncan911]

Thanks everyone.

I've lived here for around 3 years and the summer months aren't humid at all down there. It's insulated on top from the sub-flooring and it's on a slab with proper moisture control on the stem walls and under the slab/footing. During summer months it gets to about 70 F (outside 95 F).

Zero critters issue. Lots of spider issues; so yes, wire meshes have been erected on all inputs and around the expansion slots.

For now, I've disabled the HDD spindown. Power usage jumped 55W at idle.

Lowest now is 13 C, outside at -6 C.

Tonight is another night down to around -17 C. So, we'll see how it does.

 

[Deslok]

Those are some low temps but not outside of what's listed for the spec sheets at least inside...
(this was pulled from a barracuda 7200.12 spec sheet i had on hand)
Ambient temperature 0° to 60°C (operating) –40° to 70°C (nonoperating)
Temperature gradient 20°C per hour max (operating) 30°C per hour max (nonoperating)
Relative humidity 5% to 95% (operating) 5% to 95% (nonoperating)
Relative humidity gradient 30% per hour max
Wet bulb temperature 37.7°C max (operating) 40.0°C max (nonoperating)
Altitude, operating –304.8 m to 3,048 m (–1000 ft. to 10,000+ ft.)
Altitude, nonoperating (below mean sea level, max) –304.8 m to 12,192 m (–1000 ft. to 40,000+ ft.)

 

[tby]

The cold may not actually kill your drives this instant but the low temp is probably recorded in the SMART log and you could have trouble with an RMA in the future if you go under the minimum. Something else to consider is that the rest of your components may have more conservative specs. My hard drives are 5-55C but the server is 10-35C.

I keep my rack in the far corner of a ~650sqft detached garage... was -5C outside this morning and recorded a low of 7C outside the rack. Presumably higher inside the rack since it's enclosed with no fans. Don't see many days this cold and it all survived last winter so I don't worry about it. If I had much exposure to colder weather I'd probably shove some insulation in there and seal it up, or just shut it down during the colder nights.