Is it just a popping noise?
if so, this is very normal. Even if the popping noise is very loud or seems scary. This is the effect of the PG (Propylene Glycol) expanding via heat being delivered to the coil. This is typical for low resistance and sub-ohm coils, especially when they’re fresh. Also, the popping sound will be much louder with sub ohm coils.
Is it a popping noise with spit back?
In addition to the above, there will also be e-liquid lingering in the vapor chimney of the tank, which is an indication of a flooded coil. If this is the case, you may have to change the coil entirely. Some flooded coils can be "revived" by thoroughly rinsing under warm water and leaving to dry overnight, however, this is not always the case.
Is there an Electrical “shock” sensation from the tip of the mouthpiece?
If so, this means that a short in the device may be occurring. First and foremost, check that you are using compatible hardware. After that, you may need to install and prime a new coil. You can always contact our customer support team via email at firstname.lastname@example.org, via live chat, or by phone at (877) 565-8273 if you need any suggestions on power settings for your device or if you have any other questions or concerns regarding your device.