What is convection vs conduction heating, and why is this important in a vaporizer?

"I hear the Pax vaporizer is conduction. Why is the FireFly better?"

Great question!

Conduction is the heating of a substance that is in direct contact with the heat source. Convection is heating of a substance by the transfer of heat from air particles. The Pax vaporizer uses conduction, while the FireFly uses convection.

Both methods of heating have advantages and disadvantages for the purpose of vaporizers. For the purposes of this discussion, we will assume you are vaporizing shredded flowers.

It is typically faster to heat by conduction (although, while the Pax takes approximately 30s to heat up, the Firefly only takes 3s) and conduction vaporizers are easier to construct; therefore, conduction devices are usually cheaper. The medicine will have to be stirred between draws, because only the herb touching the conductive surface is vaporized. Conductive vaporizers have a greater likelihood of combusting the herbs, which is what we are trying to avoid (unhealthy bi-products of combustion).

Convective heating typically takes longer (again, not in the case of the FireFly). Convection vaporizers are more sophisticated and are usually more expensive. Convective vaporizers work better with shredded flower that is not packed into the bowl, so that the heated air can come into more contact (greater surface area) with the flower. The herbs do not need to be stirred to vaporize all of them. Convective vaporizers are less likely to cause combustion than conductive vaporizers and have more accurate temperature control.


Imo Firefly is 100% better than pax because pax is conduction and Firefly is convection. Conduction is heating up your material the whole time it’s heating up so whether it’s 30 seconds like pax or 2 to 3 minutes like other vaporizers that whole time it’s heating up your material being wasted. Alot of the terpenes and other compounds from the plant are being literally wasted because you aren’t inhaling the whole time you are waiting for it to be ready to be hit. Firefly 2 has a 3 second heat up time but those 3 seconds of heat up time your material isn’t being cooked at all because it doesn’t work untill you start inhaling. Your inhalation is what’s causing air to go threw the material and turn it into vapor so you get 100% everything from the plant itself every single time no need to rush and medicate. The pax 2 when it finallly heats up let’s say u take 4 hits and keep it in for like 10 seconds before exhaling that whole time the pax is cooking your herbs while you are trying to enjoy that vapor u just inhaled but it with the Firefly 2 no need to worry about that just inhale and enjoy no need to worry about wastage. Firefly 2 will conserve your material and get you higher everytime


The problem with conduction is that some of your herb is in direct contact with the heating element. The part that is in contact will vaporize first but heat is still required to vaporize the rest of the bowel. This leads to some of the herb cooking more than it needs to and an unpleasant taste a bit like burnt popcorn.

The firefly works by convection – hot air heats the herb and if packed correctly everything should vaporize evenly. This is why it was been rated as one of the best tasting portable vaporizers on the market.


Conduction vaporizers heat up the bud whether or not you are vaping. The oven heats up which means turn it on a minute vs seconds later you start vaping and the oven cooks the bud the whole time it’s on so the Pax is a session vaporizer so you can’t really take a couple pulls and try again later vs on demand hits which you get with the fly.


Hello there! This is a good question to ask, and definitely a key factor to have in mind when browsing for a shiny, new vaporizer. As Doctor Edmunds very thoroughly explained, conduction is the transfer of thermal energy (heat) to a substance of choice through its directs contact to a solid heat source, while convection is that same transfer of heat through the contact with a liquid or gas which is moving in order to reach the substance that wants to be eventually heated.

You can think of it like this. Let’s say that Adam is dribbling his basketball around the court and he wants to pass it to his friend Bob, but he couldn’t do it directly himself. He has two options. The first option would be lining up five of his teammates so that they could pass each other the ball one by one until it reached Bob. The other option would be to pass the ball to one particular friend, Carlos, who would then dribble it through the court and then pass it to Bob.

There are pros and cons to both options. The first option has more middlemen, who in turn could do something unexpected to the ball; for example set it on fire. I don’t know about you, but nobody I know wants a fiery ball. This is also the case with combustion, since when you heat up a solid the distribution does not tend to be particularly even, so there is a higher probability of your burning part of your medication. Since in convection one raises the temperature of the gas evenly to a certain degree before it comes in contact with the substance, the probability of burning your herb is practically null.

However, getting those ‘five friends’ to do a low effort task will probably be easier and faster than it would be to convince Carlos to run all the way to Bob and pass the ball. Conduction tends to take a lot less time to happen than convection does (although this is not the case with the firefly) since there is no travel time and the amount of energy that it takes to heat up the solid (usually metal) is also less than the amount needed to heat of the gas.

As I hinted at before, Carlos might not be so easy to convince to take the ball all the way to Bob’s side of the court, so you might need to give him some of your extra cash in order for him to actually do it. This also tends to be the case with equipment that uses convection, since more complicated energy transfers lead to higher prices.

At the end of the day a lot of it comes down to personal preference, but in terms of evenness of heating and accurate temperature of vaporization convection usually takes the cake (or ball, if we’re still following that analogy).

The real takeaways from this unnecessarily long answer are that science can be sort of cool, and you should never set your friend’s ball on fire. That’s just a dick move.

Be well!



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