Getting a Pot Still to Reflux

[eStill]

Wow. Haven't posted in about 2 years!

My pot still consists of a 20L tea urn, with a 22mm pipe up from the lid, leading to a liebig condenser at 45 degrees.
The urn has a 2kW element, but I reduce the power to 25%-50%.
I've cut the vertical column and patched in a 1m length of 28mm diameter pipe. I've filled the pipe with ceramic raschig rings.

CompleteStill.jpg

- Should the extra surface area and height cause any useful / measurable amount of reflux to happen?
- What will be the effect (if any) of going from 22mm above the boiler to 28mm for the column and back down to 22mm just before the condenser? (The condenser core is actually 15mm.)
- Will there be any additional (useful) effect if I add a few turns of 8mm copper pipe at the top of the column (before the vapour turns the corner into the condenser) and run cold water through that?

Comments on design would be great, please.