Regarding the debate of a jacket or coil..........
This is based on the Home Brew Market so the smaller conical.
There has I believe (to my knowledge) only a couple of manufactures that has made a cooling jacket for a conical, these being Willis
viewtopic.php?f=6&t=61967&hilit=+willis and the More Beer ones.
I let you read the Willis thread and the More Beer things are expensive.
So that then leaves you with the option of getting one reto-fitted or made from scratch, which money willing anything is possible.
So why not use an internal coil mounted through the lid? from a sales point of view you can then just sell the conical with a range of lid options for those who want to use a fridge to those who choose to a maxi set up to those who choose to do something else (coil wrapped on the outside like a jacket).
Is the coil a difficult thing to clean? simple answer is NO & if anyone struggles cleaning that one it would suggest that you go back & revisit the basic principals of cleaning. Again this is for a smallish homebrew conical NOT a large industrial effort.
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