# Vape coil guide: ohms, watts and wear > Vape coil explained: what the ohm figure means, the wattage that suits each resistance, priming a new one, spotting wear and making it last longer. A burnt taste, vapour that has quietly collapsed, liquid seeping up through the airflow: in most cases a single component is responsible. The **vape coil** concentrates flavour delivery, vapour volume and throat sensation all in one small part. Badly chosen or badly looked after, it ruins the best bottle on the shelf. Properly matched, you forget it is there at all. ## What a vape coil is and what the ohm figure means A **vape coil** is the part that heats the liquid and turns it into vapour. It is made of a resistive wire wrapped or printed around an absorbent wick, usually cotton, which draws liquid in from the tank. Its value, expressed in ohms, describes how easily current passes through it. That single number sets the power it wants and, by extension, the kind of draw you get from it. Two families split the market. Coils above 1 ohm aim at a tight, cigarette like draw with modest vapour. Coils below 1 ohm, described as sub ohm, produce far more vapour and an airy draw. British hardware skews towards the first family. Since refillable tanks sold here are capped at 2 ml and nicotine containing bottles at 20 mg/ml in 10 ml, mouth to lung setups dominate the shelves and higher resistance coils remain the default rather than a niche. Mesh has become the standard construction in both families. Instead of a wound wire, a perforated strip heats a wider surface of cotton evenly, which ramps up faster and tends to give a cleaner flavour than an equivalent wound coil. ## Choosing a vape coil for the draw you want The ohm value is printed on the side of the coil, usually next to a wattage range. Respecting that range is the single most important habit for avoiding a burnt taste. | Resistance | Suggested power | Draw | |---|---|---| | 1.0 to 1.6 ohm | 8 to 15 W | Tight mouth to lung | | 0.8 to 1.0 ohm | 12 to 18 W | Restricted mouth to lung | | 0.4 to 0.8 ohm | 15 to 30 W | Restricted direct lung | | Below 0.3 ohm | 40 W and above | Airy direct lung | Staying at the low end of the range preserves the cotton and the flavour. Pushing towards the top gives more vapour at the cost of noticeably faster wear, and on sweet liquids that difference can be a matter of days. One detail on the label is worth checking before you buy a pack. Two coils of the same resistance from different ranges can carry very different wattage windows, because the mesh surface and the wicking ports are not the same size. The ohm figure alone does not describe the part. The liquid has to follow the coil, not the other way round. A thin 50/50 base wicks properly into a high resistance coil, while a glycerine heavy 70/30 needs the larger wicking ports of a sub ohm build to keep up. Getting that pairing right, as our [e-liquid mixing chart](/uk/e-liquid-mixing-chart/) sets out, prevents most dry hits before they happen. ## Priming a new coil so the first puff is not the last A new coil arrives dry. Firing it without preparation carbonises the cotton in a single puff, and no amount of soaking afterwards will bring it back. - Put a few drops of liquid directly onto the visible cotton through the wicking ports, until they darken. - Fill the tank and leave it standing for five to ten minutes. - Start a few watts below the suggested value rather than at the top of the range. - Take two or three gentle draws before settling at your usual power. That standing time is the step people skip, and it is the one that matters most. Cotton takes minutes rather than seconds to saturate fully, particularly with a thicker glycerine rich liquid. ## When to change a vape coil, and the signs of wear Three signals announce the end. A toasted cotton taste, a clear drop in vapour, or liquid in the tank going noticeably darker than it started. A burnt taste that persists on a full tank means a coil at the end of its life or one that was never primed properly. Changing it at the first sign is worth doing, because a dying coil ruins the taste of every bottle you put through it afterwards. Do the swap cold, with the tank emptied. Unscrew the old one, prime the new one on the bench, refill, and let it stand again before firing. Rushing that last part is how a brand new coil gets wasted in a minute. There is a subtler failure worth knowing. Before it tastes burnt, a tired coil mutes flavour, which is easily mistaken for palate fatigue. Our guide on how to [choose an e-liquid flavour](/uk/choose-e-liquid-flavour/) explains how to tell the two apart. ## Making a coil last longer A coil typically lasts somewhere between one and three weeks, depending on power, liquid and how often it is used. That spread is wide because the variables genuinely matter that much. Sweetened liquids are the main culprit. Sucralose and heavy caramel notes caramelise onto the wire, leaving a dark crust that blocks heat transfer and dulls flavour long before the cotton itself gives up. A few habits stretch the interval. Stay at the low end of the wattage range, avoid firing when the tank is nearly empty, let the cotton rewet for a moment between draws, and keep the sweetest bottles for occasional use rather than all day. It is worth keeping a note of how long each one lasted, alongside the bottle that was in the tank at the time. After three or four coils the pattern usually becomes obvious, and it is almost always a particular liquid rather than the hardware that is doing the damage. Rinsing a coil under a tap is a persistent piece of folklore that rarely helps. Once the crust has formed on the wire, it is baked on, and a rinse mostly waterlogs the cotton. Buying coils in packs and keeping a spare in the bag is the more reliable answer, particularly for anyone starting out with the sort of setup described in our guide to [e-liquid for beginners](/uk/best-e-liquid-for-beginners/). ## Frequently asked questions ### How do I know when a coil is dead? A burnt taste that persists on a full tank, a clear drop in vapour, or liquid darkening quickly in the tank all point the same way. Replacement is the only real fix at that stage. ### What wattage suits which resistance? Follow the range printed on the coil: roughly 8 to 15 W above 1 ohm, 15 to 30 W between 0.4 and 0.8 ohm, and 40 W upwards for sub ohm builds. The low end of the range preserves flavour. ### How do I choose the right one for my tank? Start from the draw you want, tight above 1 ohm or airy below it, then check compatibility with your specific tank, since coil heads are rarely interchangeable between brands. ### How often should a coil be replaced? Typically every one to three weeks, but a burnt taste or a drop in vapour calls for an immediate change whatever the calendar says. ### Why do sweet liquids wear coils out faster? Sweeteners caramelise onto the heating element and form a crust that blocks heat transfer. The cotton may still be fine while the flavour has already gone flat. ## The short version One number does most of the work. The resistance printed on the side tells you what draw to expect, what power to feed it and, indirectly, which base ratio belongs in the tank above it. Everything else is habit. Prime properly and give the cotton its few minutes, run at the low end of the suggested range, keep the sweetest bottles for occasional use, and change at the first hint of a toasted taste rather than pushing on. Treated that way, a **vape coil** becomes the least interesting part of the setup, which is exactly what you want from it. Editorial content for adult readers only. Vaping products usually contain nicotine, a substance that causes addiction. Not for sale to under-18s in the United Kingdom. This article is not a buying recommendation.