I've been reading this thread and don't understand if you guys are putting your AVS together properly with a 901 Atty on it why you having these problems other then sometimes the Atty itself can be to tight of a draw type of Atty which will bring to much juice into it, then switch that Atty for a lighter more airy draw one so it doesnt flood but for the most part a clean overflow tank with a freshly filled top tank gets me through a few days of use refilling time and time again until I have to draw the juice from my bottom tank with a syringe only then put back together shoot what I get from the syringe back into the top tank and fill to the top and start vaping again.
I see this exactly opposite. The light airy drawing atties flood easily and the tighter ones work perfectly. Everyone uses this thing so differently its absolutely amazing to me that it does work at all.
When we were doing the testing with the beta tank and using the 901s original vent hole for feeding it was clear to me then that the airy atties did not work well with this type of system. That is where the adjustable draw and liquid lock came in.
If I took the lid off the tank with the vent hole inside the tank covered with juice it would just drain right out through the center pole down into my Grant (That was the only cartomizer device I had at the time). The vacuum pressure of the lid was holding the juice inside the tank like holding your finger on top of a straw full of liquid. The liquid lock was intended to stop the siphon effect by holding the pressure on the bottom end of that straw.
If you have one of these airy drawing atties it is like having a big gulp straw versus a tighter drawing atty that's more like a coffee stirrer. We are only trying to get a tiny little bit of juice on each puff. That balance is so hard to keep when your battery voltage is constantly dropping and your atty is getting more and more clogged as you use it.
Cartomizers were the end of these troubles and I thank you for getting me to try them.... long before the thread was started....