I've been doing this thing for about 8 months now and had some really good beers come out of it - won a homebrew "people's choice" competition at work last week with a dark lager; pretty jazzed about that.
I haven't paid close attention to how long it takes to chill down the wort until this last weekend. I did another batch (5gal) of dark lager and it took right at an hour with the immersion chiller running with strong flow throughout and with the kettle sitting on/in an ice bath to help speed it up. I've been using the IC since my second batch back in January (the first one I just sat on ice and allowed to chill on it's own.)
My questions are these:
-- Is 1 hour normal for IC chilling? I'd expect it to be in the 30-ish minute range.
-- The water coming out of the IC was cold. I'd think with good heat transfer it'd be at least room temperature, it not warmer... especially at first.
-- The water is coming from a tap and coming out at full flow. I'm wondering if the water isn't spending enough time to pick up heat transfer on the way through the chiller and I should back off the pressure.
-- I haven't tried chilling the chiller before submersion.
-- I picked up an immersible pump so I could recirculate ice water through the chiller. That'd save on the water bill for sure but it seems like if it's working properly the water temp would drop over time.
Any help would be greatly appreciated.
in terms of time YMMV, a. in terms of the temp coming out of the cooling water, the faster the COOLING water flow the lower the COOLING water outlet temperature will be. however the faster the COOLING water flow, the faster you will get cold wort. you just use more water to do that.
so assume you leave the heat source on your wort such that it's temperature is maintained constant your cooling water will have a Tin (tap temp) and a Tout at flow rate F1. now double your cooling flow rate. tin will not drop but tout will ( a new narrower delta t), assuming that the heat source temp is maintained.
a better example would be to have very cold fast moving cooling water, and throttle your wort flow (now source temp is not being maintained as we are trying to cool this) you could throttle your wort flow to a trickle and with fast cold cooling the wort coming out of the chiller after one pass would approach your tap temp and the outlet of the cooling water would be very close to the tap temp. if you then doubled your wort flow, the outlet of the wort will not be as cold, and the outlet of the cooling water will be warmer,