Not sure what you mean by not touching. I think you mean coil to coil. I have a herms system with a SS immersion chiller and the coils are tightly wound and do touch. The coil is fully immersed and i recirculate the hlt water to help with the heat transfer. It works fine as is and the temp control is good, i can perform a mash out in like 15 min. I guess having the coils spaced out would help, but if you consider the surface area of the coil minus the area from the line contact of an adjacent coil its probably negligible. My opinion. Let it ride. It did take me 4-5 batches to dial in the system, there are more important players. If i just rambled on because i misinterpreted your question, sorry, had a long day! Good luck.