I am no expert - basically know nothing about distillation - but doesn't a thumper create a potential problem if that component gets blocked? You then transform what is an open system into closed one with an enormous amount of pressure and a significant amount of flammable alcohol. I would think - but as I say I know nothing - - that the last thing you want with heat, metal and alcohol is pressure... What is the function of this "thumper"? Is it to "double distill" your wine or beer?
Wanting to stay on TOPIC... I will answer this in hopes we do not go down scenario hwy about flash point and so on.
No for one, the first run would not light if I were to touch a lighter to it, the second run prob not as well. Albeit the the heads would, if separated and allowed to fume without circulation. EDIT> The first run would be flammable as would the second. So electric element is a good idea as mentioned.
That being stated, I would heat with a HERMS an electric burner outside or in the shed or garage. Plenty of air. Now the Still heats to a temp where the desired liquid will turn to condensation and travel up a tube and again to the Thumper, very slight chance of a clog from that.
Now in the Thumper where you might want to add Juniper berries (for example) that again is the tube is on the top and what escapes there into the worm where it is chilled and converts back to liquid.
EDIT> (The Thumpers In feed tube goes to the bottom of the Thumper where the distillate is then introduced and should travel through an ABV flavored or adding berries. THIS is where the system closed,. This system and the booze there with in heated, or staying hot enough not to collapse the distillate back to liquid form as you want it to then travel out the top hole into the Worm "coil")
However-Chances of a berry climbing into the tube would be quite an anomaly. Unless the Distillate cooled so much as to stay in the Thumper, and fill. You would not see any drips or flow out of the worm and should be understanding of a problem, IF it were to explode or vent with open flame that would be dangerous.
Where the final step is. EDIT (to the Chilled Worm)
Then a drip into a vessel that has adequate air flow.
So the Thumper that GreyWolf shared (from another thread about a Thumper) he heats up to bring to temp, could indeed be kept (at temp) via burner and HERMS or as he does it (from what I gather) is pre heat and let the primary (for brewer thinking) or Stil Pot do the work of a top of the heat chart temp to carry over. You prob read the other thread and replied here. New to all of this hence the questions