Wort Chiller questions

Hey, I'm looking to move my brewing setup to the garage, so I'd rather not bring my 5 gallon boils back in the house to chill in the sink. I'm looking at wort chillers, and I'm wondering about the materials used to make them. How does stainless steel compare to copper? I assume copper is better than stainless (more people seem to use them), but why?

Edit: Looking at immersion, not counterflow.

 

Heat transfer with copper is much better than stainless.

 

Yup, copper is a much better conductor than stainless.

 

Is that pretty much the only difference? Either one more durable than the other?

 

Copper is going to be softer and easier to crease or bend. However, being a better conducter of heat, it is better suited to the task. Chilling wort is not a contact sport, so denting or bending a copper chiller is not likely unless you are banging it around. Even so, with minor dents, you will probably not notice any loss of performance.

 

Stainless steel is much more durable. The copper will likely only last your lifetime, your children's lifetime and maybe a bit past your grandchildren's lifetime. Stainless still is likely to last much longer. Just how long do you intend to keep brewing?

 

If you do some searches you will find threads discussing whether the difference between heat transfer in coper or SS matters. I have no experience with copper but our SS immersion chiller works pretty fast. The water temp matters a lot more than SS vs copper. 15-20 minutes to get the wort down to 70° a couple months ago, about 10-15 now that the water going in is cooler.