I'm looking to build a glycol chiller for six jacketed fermenters. I've seen a fair deal of home projects in which people have ripped apart an air conditioner and set the condenser coils in a cooler filled with glycol. This strikes me as inefficient. I'm looking to build my own chiller, but have a long ways to go in understanding exactly how to go about implementing my idea.
Anyway, here is the idea: utilize a tube-in-tube counterflow wort chiller (copper in copper). The inside tube is charged with refrigerant, the outside tube has glycol. Glycol from a reservoir would be pumped into the outer tube and on to a distribution manifold when a tank is getting too warm. The compressor would fire up, and cool the glycol. Both the compressor and the pump circulating the glycol would shut off when the tanks don't need to give off some of their heat.
In general, I don't think the heat added to the reservoir would be all that significant. If we're talking a few degrees here and there, I think that could more than be offset by the counterflow chilling. Now if I were to crash all the fermenters at the same time, I would be looking at around a 40 degree difference in each tank. With 6 tanks, I'm thinking I would need a pretty hefty compressor.
Sound like a good idea?
I know that there has to be a way for the heat generated to escape the system. Is there any good use for the heat from the evaporator coils?
Any idea on how long of a tube-in-tube system I would need? 25 feet? 50 feet?
Any input or guidance would be greatly appreciated.