High VG base= More coil gunk?

[BadNewsBert]

I recently switched from a 50/50 PG/VG base recipe to an 80/20 VG/DW base. Ever since this change I can't go a whole day without having to replace my coil. It gunks up and turns my liquid brown and ill-tasting after just 6 hours of use. I am using pro-tank heads rebuilt with 32AWG Kanthal and cotton wicking. I could usually go at least two or three days without needing to replace or clean a coil on the PG/VG mix.

Has anyone else had similar issues or have any advice? I am so frustrated with this right now, it is simply irritating. I am looking to go low PG or no PG for my base mix without these adverse effects, if anyone could recommend a decent base recipe that wicks well and doesn't gunk up coils quickly it would be much appreciated. Thanks!

 

[Thomasis]

Yes, I have had similar issues as you describe and my problem turned out to be the source of my VG. While I still get darkening of my liquid, I'm not having to change the coils everyday. I'm using a 70vg/30pg mix, most of the darkening is actually coming from my tobacco flavorings now BUT my biggest problem was the VG with gunky coils. I am replacing coils about once a week. Try a small order of VG from a different vendor and see if that's your issue. I don't want to post the said vendor I had VG issues with but if you PM me I will be happy to share that info with you.

 

[yzer]

Vaporized glycerin (VG) leaves no residue behind. It will break down only after it is burned to the point of breakdown at about 1000 C degrees. It's the additives like nicotine and flavoring that darken juice, foul coils and darken filler material and wicks after many heating cycles.

I use unflavored 95/5 VG/H2O. I can run cartos with this for about a week to ten days (or for about 18ml) before the juice in a carto tank starts to darken. That's when I change out the carto.

 

[Interpim]

I use 100% vg with a protank, I also rebuild my coils, but I use silica wick instead of cotton. I usually get a week or more out of a coil.