Gas range pot still

[juniperlover]

Alright, so I've had two successful stripping runs thus far, each yielding 110-proof. Just wanted to ask a couple of questions.
Often I see on here that people are measuring their runs based on wattage, etc. But on a gas range how do I do this? What I've been doing so far is load up my pot, seal up the lid with a flour paste, and crank it on high till it boils, then back it down to medium. Is this an effective way to do it?

Also, I was originally using a coil/worm condenser and would judge when to start running the water by how far the head was running down the lyne arm, but I just upgraded to a liebig and want to know when I should start running the coolant through.

Thanks in advance!