What is the best extraction system for small-batch roasters?

Managing smoke is one of the biggest challenges for small-batch roasters. Machines like the Aillio Bullet move far more air than most people expect, and without the right setup the room fills quickly. Good extraction protects the roaster, stops moisture finding its way into the machine, and avoids any airflow changes that could affect the roast itself.

Aillio’s guidance is clear. They’ve seen damage caused by people attaching long tubes directly to the back of the roaster. Moisture from the early drying stage, or condensation from outdoors, collects inside those tubes and drips back into the machine. Over time this shows up in the chaff collector, the rear fan and the back plate. The safest approach is simple: never hard-connect a powered fan to the Bullet’s exhaust. Leave an air gap so the roaster can move air the way it’s designed to.

Here’s an overview of the most common extraction setups used today - from DIY builds to a fully self-contained smoke-removal unit.

Homemade solutions

DIY setups remain popular because they’re cheap, flexible and surprisingly effective. The simplest version is a basic hood built from a heat-resistant box or container with a flange fitted to the side. Suspended above the exhaust, it pulls smoke upward before it spreads through the room.

Some roasters add computer fans or low-cost inline fans, and run a short duct out of a window using an improvised insert made from cardboard or plywood. It’s not the prettiest solution, but it offers a lot of control and keeps oily residue away from your workspace. Many people notice how much brown, sticky material builds up inside the hood - a clear sign the system is doing something useful.

A setup like this can cost as little as £15–£20 if you already have a few parts to hand.

3D-printed adapters from Aillio

Aillio provides 3D print files for passive exhaust adapters that help guide smoke upward without creating a sealed connection. They sit just above the roaster and keep airflow completely natural, which avoids moisture building up in the tube and prevents any pressure issues that could interfere with your roast curve. Many people harden the print material in the oven to improve heat resistance. 

These adapters sit neatly between DIY hoods and more structured systems.

Budget to mid-range options: AC Infinity Cloudline A4 & Pro S6

The AC Infinity Cloudline A4 and Cloudline Pro S6 are the most widely used affordable extraction options for home and small-batch roasting.

Cloudline A4: compact, quiet and efficient. Used with 100 mm flexible aluminium ducting, it gives you a simple window-vent setup for light to moderate smoke. Position the fan a few centimetres above the exhaust rather than attaching it directly, so the roaster’s own airflow isn’t disturbed.

Cloudline Pro S6: a stronger fan with more airflow for people roasting back-to-back batches. A splitter can be used to draw air from both the main exhaust and the cooling tray. Solid ducting helps keep airflow smooth and easier to clean. Always maintain an air gap so you don’t pull heat away from the roast.

They offer strong airflow at a sensible price, which is why so many small-batch roasters use them. 

Premium option (£1,378): DiFluid AirWave smoke-removal system

For those who want a plug-and-play, duct-free solution, the DiFluid AirWave stands out. Instead of venting smoke outdoors, it uses a high-temperature clean-air process inside the unit to break down smoke and odours. The result is a much clearer room without the need for any window insert, tubing or external vent.

It removes up to 99.9% of fine particles and VOCs, handles heavy smoke and slots easily into small roasting spaces. Because nothing connects to the roaster, there’s no risk of moisture travelling back into the machine or altering how the roaster moves air. It’s especially useful in apartments, well-sealed buildings or shared spaces where installing ducting isn’t possible. 

It’s the most expensive system here, but also the cleanest and least demanding to use.