Your tank has 3 pieces: the main body of the tank, the base, and the coil unit. When you fill the tank, you are removing the base and the coil unit is screwed into that (it's the little tube/chimney thing sticking up into the tank). You remove the coil unit by simply twisting counterclockwise on the little tube - it will unscrew from the base.
These are manufactured to be disposable. You can clean them in water and/or alcohol (vodka) and some people actually rebuild the little coils inside of them, but don't worry about all of that - we just want to see if your coil unit is dead or if you have a problem with the base making connection with the battery.
What you adjusted was the center pin - the thing that makes contact with the battery. It shouldn't be a problem to have loosened it, but it just needs to be poking its nose past its casing.
It's a wonderful world of little things to adjust or reposition, but don't think that this is an everyday thing to have to do. Your new tank just may have to be tweaked this once or you've got a bad coil unit, which, sadly, happens with them. This will all be second nature to you in, like, a week and then it's easy peasy to diagnose your gear and 4 seconds to fix anything that comes up.