Central cooling and heating loops for multiple fermentors

[bergerrings]

Hey everyone!

My fermentation setup consists of a heated glycol loop and a cooled glycol loop which is circulated though jackets on each of my fermentors. The heated glycol is stored in a keg which I have converted into a giant RIMS tube and flows into a pump, so two outputs. The cooled glycol sits inside several vessels inside a freezer and then flows into another pump, so one output. The glycol loops run into separate valve manifolds which direct the glycol to the desired fermentor. So for each fermentor the following outputs need to be used:
Heating pump
Heating element
Hot side valve
Cooling pump
Cold side valve

Currently I have each fermentor as a process with several states which just loop around a temperature and short countdown timer (to allow the valves to open fully before the pump starts up), so only direct on/off used. I have multiple config files saved at different temperatures so I just load up the appropriate file and start the process.

I was wondering if there is a way that I could put the fermentors under PID of hysteresis control? The main obstacle I see is that only one output can be asserted per PID and due to the one pump being used for all the fermentors, I don’t think that wiring several items into the one output will work. I feel like this is needlessly complex but I cannot figure out a better way to do this.

Hope someone can help!

[bergerrings]

I had another look at this last night and still came up with nothing.

Does anyone have any ideas on this....at all?

Damo