I did this upgrade back in '01 on our first Brewery. We originally had separate pumps, reservior, etc. and it was terribley inefficient. Not to plug a sponsor (maybe I should?), but the folks at Pro Refrigeration (a sponsor to this site) were awesome working with me to specify a central chiller unit that would meet our requirements. The unit has operated flawlessly since installation and sits outside behind the Brewery wall. If you want efficient, their unit is all that.
Our first is a 7 Bbl Brewery with (2) FVs and (3) unjacketted Grundies. We do not have a 2nd stage assist on the heat exchanger. I ran 1.5" DIA copper pipe for all of it (thousands of sweat joints, it seemed). If I were to do that over, I would have run PVD for most of it with copper in damageable areas.
Our second is a 15 Bbl rig, and we are just finishing the installation of the piece of crap that came with the system when we bought it used. The compressor on that one is a 3 hp (3 Ph) with a 1 hp process pump and a .75 Hp re-circulation pump. They are both Goulds NPE pumps and are 3 Ph as well. The Goulds pump specs can be found on their website, but the "sweat spot" for the 1" is somewhere in the range of 30 GPM at 70 Ft of Total Dynamic Head (with a 4.75" DIA impellor). The pump is working at 53% effiiciency at that point, and you can do no more for efficiency. The pumps are centrifugal with stainless bodies and impellors.
In the 15 Bbl house, I ran 2" DIA PVC everywhere except for a 1" loop that goes out to feed the 2nd stage assist on the heat exchanger. The reservior is 300 gallons.
The solenoid size is generally determined from the Glycol In/Out prots on your tanks, but I've seen 40 Bbl tanks with 3/4" solenoids on them, which is what I' recommend. Get the ASCO Red-Hat series (from Granger or similar) and please hear me when I say get the solenoids with ZERO pressure differential. Otherwise, you'll end up burning the coil out when they won't lift on the tail end of your glycol circuit. It was a hard lesson I learned that cost us a lot of jing . Red-Hats are pretty much the standard, and a general purpose solenoid will do fine. Just remember that zero differential! (You owe me a fee already for that nugget).
Only run your pipes as high as you have to go to get to the solenoids / ports. Insulate everything or learn to love condensate (and mold). Put a ball valve just ahead of the solenoid and on the outflow of the jacket so you can isolate it for maintanence and replace the solenoid without losing your glycol. Also, run your system as a "first in, last out" system to prevent short circuiting of the Glycol in your mains. The first tank to see Glycol in teh Supply Main should be the furthest away from the reservior in the Return Main and the last to drain. This takes a little finesse when doing your pipe runs.........especially if you have long and spread out tank spacings with unique tanks.
Put a Pressure Relief Valve in the system. Coming off the pump, you should have a Pressure Reducing Vlalve set to around 15 psi to prevent the jackets from splitting unless the manufacturer has stated you can go higher. I install a redundant Pressure Relief Valve in the circuit at the end that dumps to the Glycol Return Main just in case the primary fails. Cheap insurance, really.
Install a rotary indicator or similar, a pressure gage on the Supply Main side coming out of the reservoir or chiller just ahead of your first tank, and thermometers or temp sensors on the Supply and Return Mains. Place them within a very close proximity for one stop visualization. If something goes amiss, it's great to have a little telemetry to look at to tell you "Houston, we have a problem.".
Set your Glycol mix level somewhere at the 38% - 40% by volume range and get a couple of Propylene Glycol hydrometers (anti-freeze hydros won't work.....that's ethylene glycol..........mmmmmmmm.....sweet tasting). You should be protecting to somewhere between 0F and -10F. Check it regularly..........every 3 - 6 months. Pro Refrigeration recommends a 34% by volume in their systems (they are safegaurded for freeze-up). A "pieced in" system isn't as failsafe by nature (and the fact that they're sometimes homebuilt) and running the mix a little higher prevents freezing in the line.
There are other safeguards, like placing a flow control switch between the re-circ pump and the R-22 / Glycol Heat Exchanger to prevent stopped flow from allowing freezing glycol in the Exchanger from splitting the Exhanger open and costing you $2,500 to get a new one. The Flow Controller is in series with a Temp Controller Sensor and th R-22 solenoid. If you're Glycol has no flow, or is already cold enough, then the solenoid is closed.
Just some random "Lesions Learned" from designing and installing (2) systems of my own.