Stainless steel versus copper for immersion chiller

What is the relative difference in efficiency? I don’t have a chiller now, but think the stainless steel would be more durable.

Also, I would have to use it outside and since you cannot totally close off the kettle while you’re cooling it, I’m wondering what the likelihood of getting bugs or other foreign material into the wort would be. If the wort was approaching say 80 F when something fell into it, you might get bacteria in it that could ruin a batch.

I have a stainless chiller, and I like it a lot. Though it’s not as efficient as a copper one, I don’t think the difference is really that much for our application. In addition, it’s much tougher than copper, doesn’t tarnish like copper, and is much easier to clean. I can cool a five gallon batch to 100 degrees from boiling in about ten to twelve minutes, and to around 60 degrees in a half hour or less, with 56 degree water. Good enough for me. As far as bugs getting in the wort and contaminating it, I guess it’s a risk we take when we brew outside, as I also do. I will say however, that I’ve had no problems with contamination of any sort so far.

Thanks Marty.

I’ve had both and if there was a diff it was so minimal I didn’t notice. Since there is so little diff I would go with whatever is cheapest.

In over 400 batches done outside things falling into the wort really hasn’t been a problem. For me, it’s happened maybe three or four times.

This may put you at ease as far as foreign material falling into your kettle. I purchased my kettle with a lid that had a small notch cut out of it to allow the chiller to pass through while the lid stays on the kettle. If your handy at all, I don’t see why you couldn’t remove a small bit of material from the lid on your pot and have the same feature. I you would like to know where I purchased mine just shoot me a PM.

If you already have a lid just put it on right over the chiller. Drape a rag or two soaked in Star - San over the small gap, or just cover it with foil.

I’m a copper fan. Might cost a bit more but I prefer it. Try making your own to save a few bucks. I attached an old set of washing machine hoses to mine.

The limiting factor in immersion chillers is usually not the thermal conductivity of the metal, but rather how well the wort (and to a lesser extent the cooling water) is mixed, and also the overall flow of cooling water. Stainless steel tubes can be made considerably thinner than copper which also helps a bit.

The main advantage of copper actually is that it is much easier to DIY since it can easily be bent with simple tools.