My advice would be to use the shell & tube (as long as it's not a part of the boiler or something-?) to prechill the city water with your glycol and then pipe the prechilled city water into the plate HX to chill wort.
This way you dont heat up your glycol and put a huge load on your chiller, you won't potentially push hot glycol into a fermenter, and your hot water coming out of the plate HX can be piped into your HLT for brewing or cleaning.
Just be mindful of your glycol setpoint as not to freeze your water, from my experience <28°F should be fine as long as your water is moving.
Last edited by Jephro; 11-06-2009 at 04:30 PM.
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