Not necessarily 3 phase - it could be done with single phase as this is not a rotating machine, just a resistive load. For a 6 hp boiler as stated above you're going to need 125 amp single phase service at 480 volts(for the boiler alone). Not your average residential transformer. Depends on the boiler you buy. Most installations of this size are going to be three phase, so you'd probably just want to spec a boiler for what you have available.
I do believe I have a 50 amp 220v at my Well pump which will be next to the brewhouse and where I'll get my water and power.