Jumbo82 is correct. I have a 15 gallon pot and a 25' immersion chiller. It takes approximately 20 - 25 minutes for it to cool 5.5 gallons of finished wort from boiling to 65F. I use tap water to start and switch to recirculated ice water at about 100F.
Primary/Secondary: #105 APA, #106 American Wheat
Kegged: #102 Brown, #103 Red, #104 ESB
Planned: IPA, Northern English Brown