I blew up my element by boiling it dry :(

[BillPeet]

G'day guys,

Finally got my new still up and running!
It's a pot still with 50l keg boiler, 1000mm copper column and shotgun condenser. At some point I'm intending to add a reflux condenser so I can run as CM reflux.

Anyway, just ran a vinegar cleaning run today, everything ran pretty well except for a few leaks that can be fixed easily.
I tried running it for about 1.5 hours, to make sure everything was properly cleaned out - until the RCD blew in the switchboard. When I looked a bit closer, looks like the boiler had boiled dry past the element and the element burnt itself out.
I can easily replace the element, but I was wondering whether there was anything I can do to prevent it happening again? Or just make sure I start with a big enough batch? My element is about 50mm from the bottom of the boiler.

[NZChris]

Measure the volume needed to cover the element.

If you suspect you might be going to run close to that volume, know exactly how much you have, work out how much you can safely take off and don't collect beyond that.

[RickyNZ]

Is there any disadvantage other than heat up time to adding water to ensure the element remains covered throughout the run?

[NZChris]

Depends on what you're making.

[BillPeet]

Thanks NZChris, that sounds like the way to go, easier than trying to install a level sensor or inspecting the boiler during a run.
I should be able to estimate before a run how much I'm likely to extract, based on starting ABV and estimated average distillate ABV.

[Saltbush Bill]

It's not hard to calculate..what ever is on the outside of the boiler isn't on the inside.
ABV doesn't come into it.

[SaltyStaves]

It's not hard to calculate..what ever is on the outside of the boiler isn't on the inside.

Exactly. I have a small boiler and I know precisely how much liquid is needed to keep my element submersed. Some small spirit runs come close, but I've never dipped below the top of the element.
I know my jar sizes and I don't put more empty jars on the bench than I have capacity to collect. Keeps me from going one jar too far.

[BillPeet]

Awesome, thanks guys

[Saltbush Bill]

I know my jar sizes and I don't put more empty jars on the bench than I have capacity to collect. Keeps me from going one jar too far.

KISS, simple always works best.

[Smokee]

I bought a new still last year, 16 gallon with a 5500 watt 240V element and I was concerned about this as well. I learned to add the water first. I fill up the still on my spirit runs first and allow a bit over the element. Then I add the alcohol from the stripping run which puts me way over the element. With the amount of water in the boiler already plus the water that will be left over from the stripping run I always have plenty left to keep the element covered.... add the water first.

[zach]

I installed a sight glass at my minimum operating level, so I can de-energize the upper element when there is no longer liquid visible.