What Is an Air Still and How Does It Work?

Australian legal note: In Australia, using a still of any size to distil alcohol requires an excise manufacturer licence, and the ATO does not grant licences to distil spirits for personal consumption. This guide is for education, for non-alcohol uses such as distilling water, and for licensed operations. See the ATO's page on stills for the current rules.

If you have seen a neat little unit that looks a bit like an oversized kettle and wondered what it was, there is a good chance it was an air still. What surprises many people is how compact it is, and that it needs no plumbing at all.

Here is what an air still is, how it works, how the original Air Still differs from the Air Still Pro, and who each one suits.

What is an air still?

An air still is a small electric still designed to sit on a benchtop. Like every still, it heats liquid in a boiler and condenses the vapour back into liquid. What makes it different is the cooling. Traditional stills cool the condenser with running water. An air still uses an electric fan and air, which is where the name comes from.

That one change means:

• No hoses or taps to connect
• No need to be near a sink
• No cooling water running down the drain while it works
• A much smaller footprint than a boiler and column

How an air still works, step by step

1. Heating. Liquid goes into the boiler at the base and an electric element heats it. The Still Spirits Air Still we stock is the 240V/320W model, so it plugs into a standard power point.
2. Vaporising. As the liquid heats, vapour rises up through the top of the unit.
3. Cooling. A built-in fan blows air over the condenser coils, cooling the vapour back into liquid.
4. Collecting. The condensed liquid runs out of a spout into your collection jug. If you want to filter what you collect, the single-use Air Still Carbon Cartridge is made for the Air Still Carbon Filter & Collection System.

Because the whole process happens in one compact unit with a 4 litre boiler, an air still suits small batches. If you need distilled water for appliances, cleaning or cosmetics, it is usually quicker and far less fiddly than the stovetop pot and ice method we describe in How to Make Distilled Water at Home.

Air Still vs Air Still Pro

The original Air Still

The original Air Still is the simplest way in. Still Spirits describes it as an air-cooled pot still: vapour goes up and straight to the condenser without a packed column. The box includes the head unit, the boiler and power cable, and a starter guide. You can buy it on its own or as the 4 Lt Air Still Distillation Package, which bundles the still with an Air Still Fermentation Kit. There is also an Air Still Infusion Basket that clips under the lid, where the vapour enters, to hold botanicals. It does not fit the Air Still Pro.

The Air Still Pro

The Air Still Pro is also 4 litres, but its head unit has a built-in reflux condenser and two modes. Swappable capillary tips set the output flow rate: one for pot still mode and one for reflux mode. In pot mode it carries more character through. In reflux mode it produces a cleaner, more neutral result. Its listing also describes an automatic foreshots collection vial and an automatic overheat shutdown. If you already own an Air Still, the Air Still Pro Head Unit fits the Air Still boiler. For a fuller explanation of those two styles, see Pot Still vs Reflux Still vs Air Still.

A botanical basket comes with the Air Still Pro, and a replacement Botanicals Basket is available. The Air Still Essentials kit adds a fermenter, filter and collection system, hydrometer and alcometer, but not the still itself.

Getting the most from a small-batch still

Working in small batches is a different rhythm from running a big boiler, and it suits a lot of people. A few habits help:

• Plan your runs. Because each batch is small, it pays to have your next lot of water or botanicals ready to go once the unit has cooled and been cleaned.
• Use clean glass for collecting. A clean jug or jar keeps whatever you are collecting free of taints.
• Write it down. Note the date, what went in, how long it ran and what came out. Our Record Keeping for Distilling Runs guide shows a simple way to do it.
• Measure, do not guess. The free Spirits Calculators and a good hydrometer from our hydrometers range take the guesswork out of fermentation readings.

Who an air still suits

• Apartment and small-home dwellers who have no space for a boiler and column, and no laundry tub to run hoses to.
• People who want water without the fuss for steam irons, appliances, soap making and cosmetics.
• Beginners who want to learn how distillation works on a manageable scale.
• Licensed small-batch producers who want a compact unit for trials.

It suits people less well if you need large volumes in one go. Air stills are built for small batches, so a larger licensed operation would look at a reflux system or a larger copper alembic.

The legal side of an air still

The ATO's rules on stills turn on two things: capacity and what you distil. The ATO says you can own a still with a capacity of 5 litres or less without its permission, but only if you are not using it to distil alcohol. The Air Still and Air Still Pro are both listed at 4 litres, so they sit under that line, but the exemption still depends on what you use them for. A still over 5 litres needs ATO permission to possess. And using a still of any size to distil alcohol requires an excise manufacturer licence, which the ATO does not grant for personal consumption. Before you buy any still, it is worth reading the ATO's stills page. This is general information, not legal advice.

Looking after your air still

Air stills are low maintenance, but a little care keeps them running well.

• Clean after every run. Let it cool, empty the boiler, rinse and wipe it out. Residue left to dry is much harder to shift. Our cleaners and sanitisers range has gentle options.
• Check the seals. Rubber rings, washers and lid seals wear over time. Spares include the Air Still rubber ring (Air Still only), Air Still washers and Air Still Pro silicone lid seal.
• Keep it ventilated. Give the fan room to breathe and never cover the vents.
• Never leave it unattended while it is running, like any heating appliance.
• Follow the manual for fill levels and run times.

Frequently asked questions

Does an air still need water to cool it?

No. An air still uses a fan and air to cool the condenser, so there are no cooling water lines to connect.

Can I make distilled water in an air still?

Yes. Still Spirits lists the Air Still as suitable for distilled water and hydrosols, and it is usually quicker and easier than the stovetop method.

What is the difference between the Air Still and the Air Still Pro?

The original Air Still is an air-cooled pot still. The Air Still Pro has a built-in reflux condenser and swappable capillary tips so it can run in pot still or reflux mode, and it comes with a botanical basket and an automatic foreshots collection vial.

Where can I get spare parts?

We list seals, washers, carbon cartridges and other spares online, and you can ask about them at our Laverton North and Epping stores. Browse the Still Spirits range or ask the team.