How long should it take to get a decent rolling boil in the G40?
It should take 40-60 minutes from sparging.
(Or for NZ/AU(10A): 60-90 minutes for full batch.)
A tip is to switch the G40 to 99°C (210°F) while you are doing the sparge to speed up the time it takes to get to the boil.
By the time you finish the sparge, the G40 should be close to temperature.
Note: This is automatically done when using a managed brew session in the app.