at 120V, you can go no higher than 2000W on the RIMS. And you need a 20A outlet for that.
I don't know how powerful your stove is, so I've no idea what your total power output is. I *can* tell you that 2000W will get 5.5 gallons of water from 160*F to boiling in about 25 minutes.
If you were planning for a 1500W RIMS, then that will get the same water to boil in about 35 minutes.
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