Last questions on Formaldehyde. Is it comming from a burnt wick?

[redddog]

Sorry guys. I know this topic has been absolutely murdered around here the past few weeks. I just needed clarification on 2 more points.

So if normal wicking and power variables are ignored and formaldehyde IS being produced, is it the wick that it's eminating from? Or is it from a coil that is so balls hot that it turns juice into formaldehyde?

And last, the variable that is most associated with this is voltage. It says that if voltage is kept between 3.3 - 4.8v, you should not be generating Formaldehyde. But if you're sub-ohming on a .6 ohm coil at 28 watts, you're still at around 4 volts. It seems like the sub-ohm setup would be generating exponentially higher power and thus higher temperatures but it falls in the middle of the "safe" range.

Is this correct?

 

[caramel]

My take is that, when the wick is "dry" with not enough liquid, you would have a condition where the temperature of the wick / liquid goes beyond the boiling point (of said liquid) and you would get thermal decomposition products of the liquid and/or the wick material itself.

 

[iamthevoice]

If formaldehyde is formed, it's most likely from oxidization due to incomplate combustion at the interface between the coil itself and the liquid. If the coil surface temperature exceeds the combustion temperature of PG or VG, then this reaction might take place. By plugging in some data from actual vaping (the quantity per inhale, the temperature of the coil, how long the vape is held in the mouth/lungs), you could calculate the actual quantity of any compound produced then absorbed.

But then vape users would have started complaining about the side effects by now... My two cents!

 

[Dampmaskin]

Juice gets so hot it starts breaking down into formaldehyde. The silica wicks used in the experiments can withstand dry burning conditions.

The formaldehyde production is dependent on temperature (°F / °C). Temperature is dependent on power (W), time, and cooling. And power is, in turn, dependent on voltage and resistance. So to say that voltage controls the production of formaldehyde is, shall we say incomplete.

 

[redddog]

So do lower ohm coils take more wattage to produce the same heat as higher ohm coils?

That would seem counter-intuitive to me. But what do I know?

 

[sofarsogood]

I believe Dr. F is doing some experiments to learn more about what conditions create vapor that needs to be avoided. It might turn out that vapor with bad stuff only occurs when it can also be tasted. I believe the researchers in portland were reporting on a risk where you would have to vape the bad vapor daily for years to have a measurable increased risk of anything and they aren't sure if the thing they were measuring is carcenogenic.

I'm going to keep vaping. It's only been a few months I've been on zero cigs so I'm not tampering with what works for now but eventually I might fiddle with nic or ration my vaping or even try quitting vaping for a while.

The discomforts of quitting were far easier to tolerate because I had high confidence that there would be no relapse. I'd satisfied myself that vaping could take the place of smoking. That confidence comes from knowing I can vape when and as much as I want. Vaping protects me from relapse. What's what makes it different from all the other quit smoking stratagies.

 

[Lessifer]

It's about temperature. Under "normal" operating conditions we are heating the liquid enough to "vaporize" it, which is at a lower point than combustion/thermal degradation. If you operate your atomizer at a higher temperature, you go past vapor and into, basically, smoke. Three main things effect the temperature inside an atomizer, the power(resistance and voltage), the liquid contacting the coil, and the airflow. If any of those three are not within an optimal operating limit, temperature will not be properly regulated, you get a nasty hit. In the portland letter to the NEJM, they used too much power, in a clearo with less than optimal wicking(juice to coil contact) and less than optimal airflow, and got nasty hits.

 

[Kent C]

Spreading fear and confusion with misleading formaldehyde studies « The counterfactual

These two authors wrote about e-cigarettes in November 2014 (Chemists break down e-cigarette research) and in doing so demonstrated that they are basically clueless:

Peyton agreed with Pankow. He also pointed out that the high temperatures to which the element heated e-cigarette additives—over 600 degrees celsius(1112°F)—resulted in the creation of molecules not previously seen.

Vaping is typically done at 200-260 degrees celsius, with dry puff conditions developing at around 280 degrees.

It's the super over-heating of the PG that produces substances not seen in normal or even sub-ohm vaping using a mod with temp control/rDNA-40 which limits heat by default at 450°F (232°C).

 

[Dampmaskin]

So do lower ohm coils take more wattage to produce the same heat as higher ohm coils?

That would seem counter-intuitive to me. But what do I know?

Not in itself. But lower ohm are typically bigger, so they have a larger surface area. They produce the same heat at the same wattage (because wattage is heat), but the heat is spread over a larger surface.

Lower ohm coils are also typically made with thicker wire, which gives the coil gets a higher heat capacity, so the heat moving from coil to juice is also more spread out over time.

 

[Papa Lazarou]

So do lower ohm coils take more wattage to produce the same heat as higher ohm coils?

That would seem counter-intuitive to me. But what do I know?

This was something I did the other day which attempts to explain it:

 

[kenjai1]

Hi Papa Lazarou,

This illustration is very helpful! Can you show/tell me how to derive the heat flux number?
I am using an atlantis 0.5ohm coil, 20 watts, at around 3.6v.