Heating coil in the e-cigarette - how the coil works

A heating coil – usually just called a ‘coil’ in everyday vaping – is a spiral-shaped heating wire surrounded by an absorbent wick. This wick, typically made of organic cotton, transports the e-liquid from the tank to the coil. As soon as you press the fire button, electricity flows from the battery through the wire, the heating coil heats up and the e-liquid vaporises.

The term ‘heating coil’ refers to the same component, but is used less frequently. Important: The heating coil is a consumable part. Depending on usage, e-liquid and power settings, a coil typically lasts 5 to 20 days. Factory-made coils sit in a small metal housing (coil head), which you simply screw into the atomiser. In contrast, rebuildable users employ freely wound wires, which they secure in the atomiser deck using tweezers and manually fill with cotton wool.

The heating coil works on a simple principle: electrical resistance converts electricity into heat. The resistance is measured in ohms and determines how quickly and how hot the coil becomes.

Low resistance (sub-ohm)

Coils under 1.0 ohms are usually operated at 30 to 80 watts. They produce a lot of vapour, a direct lung hit (DL) and are suitable for e-liquids with a high VG content (70/30 or higher). Typical values are 0.15 ohms or 0.3 ohms.

Higher resistance (MTL)

Coils between 1.0 and 1.8 ohms are suitable for mouth-to-lung (MTL) vaping. They run at 10 to 20 watts, produce less vapour and are characterised by an intense flavour – ideal for nicotine salts and classic tobacco or menthol e-liquids.

The most commonly used wire materials are Kanthal (robust, affordable), stainless steel (versatile), nickel and titanium (for temperature control). Mesh coils, which use a fine metal mesh instead of a single wire, heat up more evenly and often offer longer lifespan and more intense flavour.

To ensure your coil lasts a long time and delivers great flavour, it’s worth checking the following points:

• Check compatibility: Every vaporiser uses a specific coil type. The designation (e.g. GTX, PnP, Z-Coil) must match your tank or pod exactly.
• Choose resistance based on draw style: For a tight mouth-to-lung draw, go for 1.0–1.6 ohms; for a loose lung-to-lung draw, opt for sub-ohm coils below 0.5 ohms.
• Stick to the wattage range: Each coil has a recommended power range. If you exceed it, the cotton will burn; if you go below it, the flavour will suffer.
• Priming: Before your first puff, drip a few drops of e-liquid directly onto the cotton and wait 5–10 minutes until the coil is fully saturated.
• Avoid chain vaping: Take a 10–20-second break between puffs to allow fresh e-liquid to flow through.

A common mistake is continuing to use a coil despite a burnt taste. As soon as the vapour tastes harsh or burnt, the coil is at the end of its life – replacing it protects the flavour and the atomiser itself. Sweet, heavily coloured e-liquids also significantly shorten the lifespan because sugar residues build up on the heating coil.

How long does a heating coil last?

Typically 5 to 20 days, depending on power, puff frequency and e-liquid composition. Sweet or strongly flavoured e-liquids shorten the lifespan, whilst mild tobacco or menthol varieties noticeably extend it.

How can I tell when the coil needs changing?

Clear signs include a burnt or metallic taste, significantly less vapour, a ‘gurgling’ noise or leaked e-liquid. At this point, at the latest, you should replace the coil.

Can I use any coil in any atomiser?

No. Coils are designed for specific tanks or pods – the threading, diameter and electrical contacts differ. Always check the model number specified by the manufacturer on the packaging.

What is the difference between standard wire and mesh?

A classic coil consists of wire twisted into a spiral, whilst mesh consists of a fine metal grid. Mesh coils heat up more evenly, usually deliver a more intense flavour and often last longer.

Is building your own coils a good idea for beginners?

For beginners, pre-made coils are much simpler and safer. Building your own coils is only worthwhile once you have mastered resistance measurement, battery safety and materials science.

The heating coil determines how your e-cigarette tastes, vapes and draws. With the right resistance, the correct power and a bit of care, you’ll get the most out of every setup. In our selection of coils and atomiser heads, you’ll find suitable replacement coils for popular tanks and pod systems – take your time to compare the models and choose the one that suits your vaping style and your preferred e-liquid.