How does a chimney system work in practice?

If you place two to three pieces of natural charcoal (26 mm) in the chimney system, the metal body heats up to around 300–400 °C. The heat is radiated evenly downwards via the base, whilst the rising air flow escapes from the sides. This gives the tobacco a broad, even heat distribution – similar to an oven rather than a hob. Everyday benefits Longer session duration: 60–90 minutes without needing to add much more tobacco is realistic. More even smoke: no hotspot effect where one side of the tobacco burns. Fewer charcoal changes: the closed airflow saves on charcoal. No aluminium waste: an HMD is a reusable product for hundreds of sessions. When traditional foil still makes sense For very moist dark-blend tobaccos with a high molasses content, many smokers still opt for double aluminium foil because it can be pulled tighter over the tobacco and provides slightly more direct heat. Even if you frequently change tobacco brands and experiment with different moisture levels, foil offers more flexibility.

Shisha & Wasserpfeife

Chimney system for the shisha: Heat Management Device explained

Shisha fireplace system: How the Heat Management Device (HMD) works, which variants are available and what you should look out for when buying - Swiss guide.

A chimney system for the hookah replaces the traditional aluminium foil and takes over the entire heat management above the tobacco bowl. Instead of using a thin sheet of foil, which burns through quickly and develops uneven holes, you use a precision-engineered metal attachment that keeps the charcoal and tobacco neatly separated. The result: more consistent heat, fewer burnt spots, longer sessions. In this guide, you’ll learn how a chimney system works technically, which variants are suitable for which tobacco bowls, and what you should look out for when buying to ensure your setup runs smoothly.

A chimney system – also known internationally as a Heat Management Device, or HMD for short – is a metal attachment, usually made of aluminium or stainless steel, which is placed on top of the tobacco bowl. Inside is a perforated base plate, on which the charcoal rests. The surrounding rim acts like a small chimney and channels the heat downwards into the tobacco.

You should distinguish the chimney system from two related terms: a chimney attachment system generally refers to the same component, but is often used in connection with permanently integrated tobacco bowls that already incorporate a chimney principle (e.g. certain Phunnel or Vortex bowls with a heat-protection attachment). A smokebox system, on the other hand, is a compact, enclosed variant with a lid that completely encloses the charcoal and allows for particularly long sessions. All three designs solve the same basic problem: directing the heat into the tobacco in a controlled and even manner.

If you place two to three pieces of natural charcoal (26 mm) in the chimney system, the metal body heats up to around 300–400 °C. The heat is radiated evenly downwards via the base, whilst the rising air flow escapes from the sides. This gives the tobacco a broad, even heat distribution – similar to an oven rather than a hob.

Everyday benefits

Longer session duration: 60–90 minutes without needing to add much more tobacco is realistic.
More even smoke: no hotspot effect where one side of the tobacco burns.
Fewer charcoal changes: the closed airflow saves on charcoal.
No aluminium waste: an HMD is a reusable product for hundreds of sessions.

When traditional foil still makes sense

For very moist dark-blend tobaccos with a high molasses content, many smokers still opt for double aluminium foil because it can be pulled tighter over the tobacco and provides slightly more direct heat. Even if you frequently change tobacco brands and experiment with different moisture levels, foil offers more flexibility.

Not every heat management device fits every tobacco bowl. Before you order, check these points:

Compatibility with your tobacco bowl: Phunnel, Vortex and Egyptian bowls have different external dimensions. An HMD should sit on the bowl with around 2–3 mm of space, not wobble.
Material: Aluminium is lighter and heats up faster; stainless steel retains heat longer and is more robust. For beginners, aluminium is often more comfortable to use because the heat can be regulated more quickly.
Open or closed system: Open chimney systems require less charcoal and deliver more flavour per puff. Closed smokebox variants last longer and are more forgiving of mistakes in charcoal management.
Charcoal size: Most HMDs are designed for 25g or 26g cube charcoal. Check the internal dimensions before using larger 28g charcoal.
Workmanship and handle: A heat-resistant handle or a pair of charcoal tongs should be included in the set. Sharp edges on the inside are a clear sign of poor quality.

A common mistake made by beginners: the chimney system is immediately loaded with three freshly red-hot coals. This is usually too hot. Start with two coals and only add the third after 15–20 minutes, once the initial heat phase has subsided.

Do I absolutely need a chimney system?

No. Aluminium foil still works reliably. However, an HMD provides more consistency and is cheaper in the long run, as you won’t need to buy foil anymore.

How do I clean a Heat Management Device?

Once cooled, tap out the ash residue and clean the interior with a soft brush and warm water. Do not use harsh cleaning agents, as these can damage the surface.

Does an HMD fit on every hookah?

The chimney system sits on the tobacco bowl, not on the hookah itself. So the shape of the bowl is what matters, not the smoke column or the bowl.

How many coals should go in a chimney system?

For open HMDs, usually two to three 26g charcoal cubes; for closed smokeboxes, often just two. Keep an eye on how the tobacco is burning and reduce the number if the smoke becomes harsh.

A chimney system used correctly for hookah means: longer sessions, even heat and less hassle with burnt-through foil. It’s important to choose the right size for your tobacco bowl, a sturdy material and sensible charcoal management. If you want to put together a setup or expand your existing one, take a look at our windscreen and chimney systems section and compare the options. You’ll also find suitable tobacco bowls and natural charcoal in our range.