BitFury with their data tank division are the ones to talk to on immersion cooling setups. Very efficient means of moving the heat from a very compact point-A (the miner tank(s) to Point-B (outside). Large-scale of course with each tank handling several hundred THs I believe.

That be them (swamp cooling). Something else to keep in mind is that the miners do NOT need an ambient 'comfortable' for people. My main farm remains quite happy when their room gets up to 85-87F in the summer.

For a reference, CK pool is currently running ~34PHs. and today has hit 5 blocks. Yesterday they hit 11, day before that it was only 1 block. Running my 110THs they paid me 0.08 BTC per block. You do the math on earning vs the Solo Lottery and well.....

For cooling, moving outside air in and out is the best choice. Where practical, look at large-surface swamp cooling if ambient is regularly over 90F. Additional benefit is that being for all intents and purposes wet air filters the swamp cooling gives ya pretty clean air. Having free(ish) electric is great if real AC is really needed but that should be a last resort because when it comes down to it all miners are perfect heaters. All power in is expelled as heat. Please no nitpickers about micro energy sent over the 'Net etc...

I might add that @ $563 USD and 4.7THs each for s7's, 20k$ (USD) buys 35 miners for >166THs with around 45kw power usage ... Got a hunch the exchange dif between 20k USD and 20k Pounds would cover any VAT you face no?

I do have to agree with VirosaGITS on using s7's. Using the Bitmain supplies pretty much across all batches since b7 my monitoring reads 6.2A on a 208v line (1.290kw) and on the whole producing as advertised 4.7ish THs. Some a tad less, some consistently averaging >5THs. Currently $563 USD vs the Avalon6 @ $900 for 3.5THs @ 1kw ish load.

I should add that I just picked up one of the latest batch-16 with the one fan and so far it is doing fine. Ordered on Wednesday and got it the Monday after. Temps surprisingly   the same as the 2-fan ones sitting next to it.

I also MUST add that now since the foundry TSMC has had time to re-calibrate their 16nm Fab after the earthquake earlier this year I suspect that we will be seeing Bitmains miners using 16nm nodes size showing up in (hopefully) the next month or less. Unlike *some* miner chip makers <cough, BitFury> Bitmain has always been very quiet about new tech until it is actually in production with fast and on-schedule delivery. It is a cert that Bitmain's last 2-3 batches have been their Plan-B to cover their ass on any delays in 16nm chip production.

As far as I know, a company called BlockC is the only globally Authorized direct distributor of the Avalons http://www.blockc.co/ so they are the ones to talk to. Anyone else outside of China is reselling from them. BlockC is who folks here used for group buys of Avalon6's. Since they only sell in lots of 10 or more sounds perfect for your plans.

Of course they run 24x7x365. In mining it usually makes no sense to turn them on and off. Some of the supplies date back to Bitmain's Batch-2 (around a year ago?). Before the s7's came out I was mostly using HP DPS1200 server supplies for the (then smaller) farm of s3, s4, and s5's. Currently per CK pool my total average hashrate is 110THs now running mostly s7's.

Unless you run a peta-hash farm, these days solo mining is more for fun with folks using USB stick miners or other low (ish) power/hashrate device. The odds of hitting a block vs daily power costs even if near free are too high.

For the S7 and any other miner that uses less than 1400w I highly recommend Bitmains 1600w PSU. A general rule of thumb - for sustained loads eg. mining - always keep the load at 90-80% or less of a PSU rating. I have 25 of them and zero problems. Aside from that they already come with 10 PCIe connectors.

re Searing:
"But to further go into the hole on this TOY. (when in doubt and tossing money in a hole best to keep the toy/amusement factor in mind)"

Absolutely love that line of thought. Hope ya don't mind if I steal that line from time to time

Ja they are massive power -- which in turn means massive weight. As is several hundred to over 1k Lbs each so plan on needing an engine hoist or other heavy lift device to handle them...

RE here https://bitmain.zendesk.com/hc/en-us/articles/203361315-Board-Diagnostics for what you can do as basics checks -- and how to remove boards from sinks. (does NOT apply to the s7! They want the whole boards)
It is for an S4 but still applies. Somewhere they have a page on others as well...

edit:  duh, just click back a like to the Troubleshooting home https://bitmain.zendesk.com/hc/en-us/categories/200236359-Troubleshooting

without voiding the warranty you ARE however allowed to swap the controller cables around to verify a cable or socket isn't bad. It probably be something they will ask you to do so try it ahead of time to save on playing email ping-pong before they issue an RMA.

I've only had 2 problem miners, a s5 and and last Feb a s7. Both had DOA cards. Filed the repair ticket, they got back in a day or so with a few questions I answered (also had made screen shots of the GUI's showing the problem).

They got back with the RMA procedure. If you are lucky and is not all cards, the bad card(s) will need to be returned at your expense. In both cases I got a replacement card 2-3 days after UPS said the got it. Dunna know how so fast They pay the for shipping the card(s) back to you.

From the USA my cost shiping to China using UPS's cheapest international  was $75.  

That jives with what I see at work. FINALLY getting fiber into the industrial park where we are but still for now we just have bonded-T1 handling VOIP and a measly 1.75mbit dl speed Internet. The 90THs there does put a dent in that, so was thinking about putting in a 4g HotSpot. Bzzzt. Nope - to much monthly data When I looked into it think I was running 32THs and that was just under 10gb/month. I calc'ed (based on real data from s3's. Loved OpenWRT for that!) me eating around 25-30kbit. It doesn't need high bandwidth but that slow speed is non-stop 24x7x365 so adds up fast if using something with a data usage plan.

Plus most pools limit average per-miner bandwidth by controlling the difficulty. Kanno keeps it around 18 shares/sec.

And you cannot drop below around 11.7 or the miner will be very unhappy... More than anything the time it takes to drop to that is what matters and that small of a voltage swing puts you back to normal (but big) batteries.

Deep cycle batteries are designed to routinely withstand going from full charge 12+v nominal to below 8v or less @ sustained high load which would rapidly kill a normal battery. Remember, they are for trolling motors, electric pallet jacks, and RV power etc. Now if they feed an inverter or a switching buck/boost regulator to hold @ 12V out, whole different story.

edit: NM. Just read reply ^^

I wouldn't exactly say that but -- they ARE strictly in it for the money. That said, yes there have been many that pushed things too far and definitely took advantage of a market that was biting at every Shiny New Thing they announced eg, AMT/Bitmine.ch, BFL, BA et al and I am sure that there will be others. Still definitely Buyer Beware of any new company that shows up.

For now, the only ones still standing with any decent reputation for delivering product after the past 2 years of scammers are Bitmaintech, Avalon, and BitFury. Love'em or loath'em, only Bitmain and Avalon make usable miners for the general public. I leave out Inno because of the A1 is now useless and anything based on their A3 still ain't there for the public. As for the SP50...

Geeze that makes me feel old... Back in the mid 70's when I was in the Airforce I worked on some SCR switching power supplies for microwave xmitters - 10kw @ 5kvdc... Anywho the banks of scr's used the exact same heatsink design but 1 piece (a Wakfield part actually) vs 4.

Same potential problem of air bypass down the center. Perfect solution is a cone pointing inward for about 1/2 the heatsink length vs a flat plate blocking it. The cone creates a much smoother pressure distribution towards the fins, flat plate makes a lot of turbulence right where ya don't want it - at the heatsink exit.

I've harped on this issue (availability time frame) since companies 1st started making noise about 16/14nm around the end of last year. It didn't stop me from getting more s7's to replace the few s5's I still have in my farm. What did stop me was Bitmains latest 1-fan batch...