Here is my problem. My tap water in winter is still 75F, except on the few days outdoor ambient temp is sub 40F. My tap water stinks for immersion and counterflow chilling. Takes about 20-25 minutes to get 10 gallons to pitching temp with my immersion chiller. My solution has been to add a few extra feet (about 10) of hose between the faucet and the chiller, and drop that into a bucket of ice water. This works fine, gets my time down to 15ish min. It is a bit of a pain though.
I am going to move to a slightly more automated solution for chilling wort. What I have in mind is this: A large bucket with 50 or so feet of copper tubing coiled inside, fill the bucket with an ice water slurry (maybe make it supercooled), then pump the wort directly from my kettle through the inside of the copper tubing, and back into the kettle. With a large enough surface area submerged in 15 gallons of 4degreeC (or colder) water I think I can get the boil-to-pitching time under 5 minutes for 10 gallons.
The flow diagram would be-
kettle-->submerged copper coils-->pump-->kettle
The chiller could be cleaned and sanitized by placing the hose ends in a bucket of starsan and letting it circulate for several minutes and then soak. Rinse with distilled or boiled water a few minutes before the end of the boil.
Anyone have any experience with hybrid or automated chillers?