I just got an alcoengine which i think is an exact copy of the Pure Spirits column, same manufacture maybe?
The top of the column has a couple of small holes around where the condenser pipes go through the column wall; the top of the pipe is capped off.
The cap is pop riveted (copper, or at least copper colour) in place so would not be air tight.
I'm wondering if the two small holes are sufficient to let out any possible vapour?
Should i drill a couple of holes in the cap?
My, (limited) understanding is that a VM the column top should be fairly open ?