Flow Rate


I've just started my first few runs with my 5" Dash 2 six plate pro model with a 200L boiler heated with 3 x 2.4kW elements (the max I could use) and I'm interested to know what flow rate I should expect

Clearly there are a few variables but I've been running at 75% power with the dephleg at 50% - the flow rate is only 2.5L/h.

Next run will be at 100% power. Grateful for any feed back from others.



  • Not enough details.

    What's your wash ABV, what's your target output proof/abv?

    What do you mean by "dephleg at 50%"?

    5kw on 200l is a bit light on the power, especially if your goal is to run high reflux rates (and high output proof).

  • I'm aiming to use 50/50 neutral spirit and water with an initial ABV of 47.5% for the 200ltr charge. I wish to draw out the heads to about 82%ABV. The heating elements is a 3 x 2.4KW - 7.2KW in total. The system I have has a dephlegmator which I used as per the guide book - initially on and then reduced to allow the flow of spirit. I conducted a test run on a half charge of 100ltrs with a average flow rate of 2.5ltrs/hr - but I did have the power reduced to 75% and water was still running through the dephlegmator a bit; however the spirit was a pencil stream out of the parrot as per the guide. I was surprised at how slow it seemed. With that flow rate a full 200ltrs would take eternity - clearly I'm doing something wrong!

  • It's difficult to compare dephlegmator settings, there are a lot of variables involved which make trying to describe it very challenging.

    Input temp, output temp, flow rate are the variables involved. If your water is warmer than mine, you'll need more flow, for example.

    Even differences in wash ABV will make a big difference into the flow rate needed to hit a target proof. If my kettle charge is stronger than yours, I'll need less flow.

    Realistically, the easier rule of thumb is to run as little flow as possible to maintain your output proof - and not necessarily try to compare.

    You can run too much flow, meaning you are cooling your reflux too much (also known as subcooling). What I've seen lots of beginners do is try to crank up the power to try to compensate for that. More energy into the bottom of the column to compensate for too much energy taken out of the top. In this scenario, the flow rate through the column is really high - you've got lots of liquid in the drays, lots of condensate dripping down, violent plate action, but not much coming out of the business end.

    I don't know why you are loading the kettle with neutral and water, and then making a heads cut - that's a bit counterintuitive, but if you aren't aiming for 95% output - you should be able to blow out that run in 5-6 hours once distillate starts flowing.

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