Freshness Vapes
Freshness Vapes

Coils 101

In this section we go over "coils", what they are, how to use them, what the options are.

A coil is a peice of wire that is surrounded in a metal housing, wrapped with cotton. The wire that makes the coil is what heats up the E-Liquid and the cotton is what "wicks" the E-Liquid to the coil in order to be heated thus producing vapour. Coils come in 2 forms. The first form is a factory pre-built coil that does not require anything except for priming it. The second type of coil are "custom made" made coils, this is when the user gets a thin piece of wire designed for vaping, wraps the wire around a circular pin creating a coil. The user then needs to install the coil into the metal housing, check its resistance to ensure it is safe to use, dry fire, wick, prime and break in. The second form is coil is for the advanced experienced users. Factory coils are consumable items designed to be used, thrown away and replaced with a new coil.

There are 2 types of coils:

  • Factory pre-made replicable coils
  • Custom made coils

There are many different types of coils to choose from, the reason for this is some users prefer a high wattage coil with high airflow and some users prefer a low wattage coil with less air flow. The higher the wattage the coil is rated for the more power is required also meaning more E-Liquid consumption.

This is something the user needs to take into strong consideration. Putting aside PG & VG ratios in E-Liquids. Heat and power effects how much nicotine the user receives.

  • A coil that is rated at a lower ohm (eg 0.15ohm) will require much more power (possibly 100+ watts depending on the manufacturer of the coil) in order for the coil to heat up and produce vapour. In respect the more power required will translate into more vapour production, more vapour production means more nicotine delivery. A user may only require 1mg of nicotine if vaping on a low ohmage coil in order to stop the “cigge” cravings. The more power means more E-Liquid consumption.
  • A coil that is rated at a higher ohm (eg 1.50ohms) will require much less power (between 5-10 watts depending on the manufacturer of the coil) in order for the coil to heat up and produce vapour. Because there is less vapour production being produced the user will receive less nicotine delivery compared to a lower ohmage coil that produces more vapour. In this instance the user may require 9mg of nicotine delivery in order to stop the “cigge” cravings. The less power means less E-Liquid consumption.

Sub-Ohm tanks have become very popular because of their options available, ease of use, E-Liquid capacity and reliability. The user can choose coils ranging from 0.15ohms all the way up to 0.95ohms depending on the manufacturer of the tanks and coils. This allows the user to choose from a very large range of tanks and coils that may suit the user best without the need to go into “rebuildable atomizers” or a basic stick style “vape pen/starter pen style kit”.

If no Sub-Ohm tank suits the user, they have an option to choose and vape with a “rebuildable atomizer” (RDA or RTA), the user can build the coils to the specs that they desire. Though much research must be done by the user before even attempting to use a rebuildable atomizer as these types of hardware are for advanced users only.

Replacement of coils is like asking how long a piece of string is. Many factors contribute into the life expectancy of the coil, things that do reduce coil life are:

  • E-Liquids that contain high VG
  • E-Liquids that contain sweetener
  • Using the coil at high wattage or above the recommended range

Replacement of coils should be done whenever a burning or weird tastes starts developing or when it has burnt out (the mod will say "no-atomizer"). 

Brand new coils may have a cotton like taste to it this is also known as a “dry hit”, to avoid this you must ensure you coil is properly primed and always start breaking in a new coil at low wattage. If the coil still does have a cotton like taste to it, it could very likely be due to the E-Liquid that you are using. Any E-Liquid above 70VG will cause factory coils to dry hit. In this instance lower your VG content.

If you still insist in using E-Liquids that contain high VG content, you should look into rebuild-able atomizers as factory coils arent capable with E-Liquids that contain high VG.

A custom coil is when the user makes their own coil, using round wire, a coil jig then checking the resistance of the coil with an ohm reader.

Coils are a thin piece of wire or multiple wires that are wrapped around with cotton that is enclosed in a metal housing generally made out of stainless steel, some “premium” coils come with housings that are gold plated though they offer NO benefit to the user other than looks. The coil wire is generally made out of Kanthal KA1 however other types of metal are available.

The coil screws inside the tank. The cotton/wick is what holds the e-liquid and the wire is what heats up when the user presses the firing button on the mod resulting in the E-Liquid to heat up, thus producing vapour. Coils are a consumable item that are meant to be used and disposed of.

The lifetime on the coil varies, it’s like asking how long a piece of string is. There are many variables to consider such as:

  • The type of E-Liquid being used
  • The resistance of the coil
  • The wattage the coil is being used at
  • Did the user prime and break in the coil properly

E-Liquids that have:

  • High VG content
  • Artificial Sweeteners
  • Thick full bodied heavy creamy flavours

Generally cause coils to wear out faster compared to average E-Liquids that have a balanced PG/VG ratio content such as 50/50. The lower resistance coils means that higher wattage will need to used in order to produce the vapour, higher wattage = higher E-Liquid consumption = faster wear, vice versa.

NO 2 coils are the same! Each coil is unique will have some form of variation between them. Most pre-built coils on the market are manufactured in China, the housings of the coils and the coil wire are produced by machines with precision tolerances though the internals of the coils (the wire and cotton) are assembled by human beings and not robots. Each brand will produce different outcomes.

Similar like trying on a pair of shoes from 2 different brands, they look the same, the have laces, they are made from the same fabric, they have rubber soles. Though they feel very different to the foot. One feels soft and the other feels hard.

If the user was to use a sub-ohm tank from brand “ABC” with E-Liquid “123” with a result of “AAA” then used the same E-Liquid “123” in a sub ohm tank from brand “XYZ” the result might be “RRR”. Different brands of sub-ohm tanks produce different flavours and cloud production as the design of the tank and coil is different, what might be amazing to one user might not be great for another user. Vice Versa.

Please note: The term “coil” is used for factory pre-made coils that require no assembly what so ever. Some sub-ohm tanks have an option “RBA” section where the user can build their own coils to best suit them, however this is for the experienced users only.

Mouth to Lung (MTL) means the coil is generally a low wattage coil with a usable range from 5-20watts depending on the manufacturer, MTL coils usually have a resistance value of 1.20ohms-1.80ohms. MTL coils are designed for low wattage as they have a tight (narrow) pull (airflow) to it. MTL coils mimic smoking a cigarette as the user needs to inhale with the mouth first, then into the lungs. MTL coils generally require a higher mg strength of nicotine as the nicotine delivery is quiet low as MTL coils produce very little vapour and have much less E-Liquid consumption compared to a DL coil. (the more vapour the more nicotine delivery the user receives). MTL coils generally don’t use much power and can extend battery life when compared to DL coils. Also to note the most MTL coils cannot handle high VG E-Liquids. It is best to stick with 50/50 PG/VG ratios with MTL coils.

Direct Lung (DL) means the coil is generally a medium to high wattage coil with a usable range from 20-200+watts depending on the manufacturer, DL coils usually have a resistance between 0.15-0.95ohms.  Most DL coils have a resistance value of less than 1.00ohm, hence being named “sub-ohm”. DL coils have a much wider internal bore to them with much wider airflow because of this design DL coils can have a very airy pull/draw to somewhat semi-restricted. With most sub-ohm tanks on the market now they tanks have adjustable airflow. So if the user does prefer a somewhat MTL style draw/pull/drag it’s a matter of adjusting the airflow to restrict it, though the wattage will need to be lowered as the reduced airflow will create more heat and more flavour. When vaping DL style (wide open air flow) towards the higher wattage 50+ more power will be required to heat up the coil, this will produce more vapour. DL coils generally use allot of power and can drain batteries rather quickly.  Because of the higher vaper production from a sub-ohm coil the nicotine delivery will be much higher when compared to MTL coils, the user may need to lower the nicotine mg strength. Please note that sub-ohm (DL) coils can handle up to 80VG/20PG E-Liquid depending on the maker of the coil.

While it may seem confusing the user can refer to this simple pros/cons below

MTL Coils 1.2ohm-1.80ohms


  • Less E-Liquid Consumption
  • Less Battery Consumption (higher battery life)
  • Less Vapour Production (great for stealth vaping)


  • Limited to a tight draw/drag
  • Limited flavour output
  • Limited Coil Options


DL Coils 0.15ohm-0.95ohms (Sub-Ohm)


  • More Flavour Output
  • More Vapour Production
  • More Airflow Options


  • More E-Liquid Consumption
  • More Battery Consumption (less battery life)


Please note: Coils need time to be primed and broken in.

Coils must be primed before being used, if the user does not prime the coils correctly the coil will burn out. The user should replace the coil whenever changing E-Liquid flavours, tasting dry or burnt out and simply stop working. To prime a new coil the user need to saturate the cotton with E-Liquid, in order to this the user needs to apply one drop of E-Liquid at a time to the cotton until all of the cotton starts to look “wet”. This can range from 5-30+ drops depending on the manufacturer of the coil. The user should take their time doing this and not rush. The user then needs to screw the coil into the base of the tank and assemble the rest of the tank. The following steps will need to be performed once the tank is assembled:

  • The user then needs to close off the airflow completely
  • Fill up the tank with E-Liquid
  • Once full the user needs to seal off the tank (screwing the top fill mechanism back on)
  • With the airflow still closed the user should take a “dry pull” 2-3 times for 1-2 seconds (this will ensure enough E-Liquid has saturated the cotton)
  • The user can then screw the coil onto the mod
  • Open up the airflow
  • Turn the mod "ON"
  • Start at low wattage (5watts), press the firing button and inhale for 2-3 seconds then release the firing button, then exhale. Repeat this step 3-4 times. Then increase another 5watts (now up to 10watts). Keep repeating this step until the user reaches their desired preferences. This process will take some time, though it will ensure the coil has broken in properly. This process take about 1-2 tankful’s of E-Liquid, do not rush this step, always start at 5watts regardless of the resistance the coil is. Even though no vapour will be produced at 5watts on a 0.15ohm coil it is still new. The slower the user takes it, the longer the coil should last.

Please note: While breaking in the new coil, it is not unusual for the flavour to taste off and weak and produce little vapour. Most coils will work fine on a 50pg/50vg mix of E-Liquid. However some bigger tanks such is the Smok TFV4 “may” get spit back with a high PG based E-Liquid (70PG/30VG), if this is the case it is suggested to move up to a 50PG/50VG E-Liquid blend. Though this is in very rare circumstances. Do not under any circumstances go over the recommended max wattage of the coil as this will cause it to burn out.