Automated Glycol Control System Idea

Does anyone who knows electrical systems a little better that me have an idea whether this will work for a glycol control system?

I plan to wrap my fermenters with a copper coil and insulation. I would like to run a glycol loop and have motor actuated ball valves open to allow the flow of glycol through the coil when the temperature controller calls for cooling. Basically, the valve is normally closed and the glycol runs in a loop. When the fermenter temperature reaches a high temp setpoint, the valve opens and allows glycol to cool the fermenter. When it reaches the setpoint temperature, the valve closes.

I am thinking that 12v is better than 120v for this because it would be nice to have low voltage wire to the valve wrapped with the temperature probe going to fermenter from a wall mounted control panel. It seems like a typical temperature controller like this:
http://www.ebay.com/itm/10A-12V-Dig...067?pt=LH_DefaultDomain_0&hash=item27d98a0e63

will work with these motorized ball valves:
http://www.ebay.com/itm/motorized-b...532?pt=LH_DefaultDomain_2&hash=item3cd9b33a6c

Anyone see any fatal flaws or have ideas for this? Is there a reason not to use 12v equipment?

It is a sound idea, have done the same thing with glass carboys and cooling plate, https://picasaweb.google.com/110297595278760536729/CarboyCoolingSystem#5256434297933178562. The picture is an old one prior to final build. The carboy insulation used was foam rubber inside a vinyl jacket with velcro closures so coil could remain in place and carboy switched out as needed.
Cooling system is a remote water fountain cooler with a modified thermostat and water/ 15% antifreeze mixture.

I have also seen some people use a SS coil inside the conical. What will you use for adding heat?

FYI, The STC1000 you linked is commonly used for temp control on fermentation chambers, keggerators, and other applications. Should work fine.

No heating. Just cooling. Thanks for the input guys. DOes anyone have any thoughts or recommendations regarding using 12v dc equipment?

I have a similar plan, but I have a BCS-460 and a 16 output expansion board that Im going to use, I have 4 Temp inputs to use with the BCS when I'm not brewing so the idea is the temp inputs can moniter fermentations temp, the BCS will control a 3-way Solenoid valve that diverts the coolant from the cooling loop to the cooling coils around the fermenter, and a SSR that controls a brew belt for heating for each fermenter. Right now I have one, but Id like to expand to 4. As for the DC control, I was looking at this 8 relay 12vdc board from the brewtroller's site.

I think if you did not want to go the BCS route Im sure you could set something up from brewtroller that will work.

Good plan but the only thing I would suggest would be using 12vac fountain pumps to circulate and have those power cycle instead of a ball valve. So long as you balance your reservoir right you can stop and engage flow without issue. And those pumps can usually be found cheaper than the solenoid valves.

Indian_villager said:

Good plan but the only thing I would suggest would be using 12vac fountain pumps to circulate and have those power cycle instead of a ball valve. So long as you balance your reservoir right you can stop and engage flow without issue. And those pumps can usually be found cheaper than the solenoid valves.

Click to expand...

That's exactly what the Cool Zone folks are doing.

I don't see why a roll-your-own version would not work. You certainly could use a STC-1000 in place of one of the temp controllers they use in their kits.

I set this up using FermTroller, same board, different software load. works good, though there isnt much support for it. I have a developer in the wings waiting to help me set up a web portal for the thing to open up more functionality..