I've been doing 5 gallon batches in a Blichmann Boilermaker. The burner and Boilermaker are very efficient at heating up the wort. I used two 25' coils for cooling the wort and it took only 10 minutes to chill from 212 F to 64 F.
I have just finished my first 10 gallon batch in a keggle. I used the Blichmann burner under the keggle but could not sustain a vigorous boil.
I have a 3/8" OD tubing with 50 feet to chill the wort. It seemed to take forever to cool the wort.
I am looking for suggestions to heating and cooling. I would like to sustain a vigorous boil and cool the wort in about ten (10) minutes. I do like the coiled wort chiller and do all gravity brewing.