How to prime a vape coil

Why priming matters

Inside every coil is cotton wick designed to soak e-liquid and feed it onto the heating element. When the coil is in the box, that cotton is completely dry. If you install the coil and fire it immediately, the heating element heats dry cotton. Dry cotton burns. Once burnt, the cotton is permanently scorched. The coil is ruined before it has even started.

Priming is the single most important habit a vaper can learn. A 60-second oversight on a new coil costs you £2-4 every time. Across a year of regular coil changes, that adds up to real money and real frustration.

The 5-step process

1. Remove the new coil from packaging

   Take the coil out. Examine the wicking holes on the side of the coil. These are small openings where you can see white cotton. They are where e-liquid enters the coil.

2. Apply e-liquid directly to each wicking hole

   Use the dropper or fine-tip nozzle on your e-liquid bottle. Apply 4-6 drops to each wicking hole. Sub-ohm coils have larger wicking holes and need more liquid (6-8 drops). MTL coils have smaller holes (3-5 drops).

3. Watch the cotton change colour

   Dry cotton looks bright white. Saturated cotton looks translucent or slightly grey. As you apply liquid, you should see the white turning translucent. That visual change confirms the cotton is taking on liquid.

4. Install the coil and fill the tank or pod

   Screw or click the primed coil into the tank or pod. Fill with e-liquid normally (leave a small air gap).

5. Wait 5-10 minutes before first firing

   This is the step most people skip. Capillary action needs time to draw e-liquid further into the cotton from the tank reservoir. New high-VG sub-ohm coils need closer to 10 minutes. Smaller MTL coils with thinner liquid need closer to 5 minutes.

The dry pull and ramp-up

After the 5-10 minute wait, take a few extra precautions before firing at full wattage.

1. Take 2-3 dry pulls without firing

   Inhale through the mouthpiece without pressing the fire button (or, on auto-draw devices, inhale very gently). This pulls liquid further through the coil by suction. You will sometimes hear a faint click as liquid moves.

2. Set the device to the lowest recommended wattage

   Check the coil's wattage range (printed on the coil itself or on the box). Set the mod to the bottom of that range. For a 15-25W coil, set 15W.

3. Take 3-4 short gentle puffs

   Press fire and inhale gently for 1-2 seconds at a time. Short puffs. This warms the coil gradually and helps the cotton settle. Vapour will be thin at first.

4. Step the wattage up gradually

   After the gentle puffs, increase the wattage by 2-3W every few puffs until you reach the middle of the coil's recommended range. Stop at the middle. Going higher straight away shortens coil life.

Common priming mistakes

Priming different coil types

The technique adjusts slightly depending on what kind of coil you are using.

Signs of incomplete priming

If your new coil tastes off in the first few puffs, the wick was not fully saturated.

• Slight burnt edge on the flavour: Cotton was partially burnt on first firing. Coil is still usable but may have reduced life.
• Persistent burnt taste: Cotton scorched on first firing. Coil is permanently damaged. Replace and prime properly next time.
• Weak or no flavour: Wick is dry. Stop firing. Wait another 10 minutes. Take dry pulls. Try again at low wattage.
• Crackling and gurgling but no burnt taste: Wick is over-saturated. Flick excess liquid out (mouthpiece down over tissue) and take dry puffs.
• Thin vapour at the right wattage: Cotton was wet but not fully saturated. Take a break, let it sit upright, try again in 5 minutes.

The bottom line