What is a Bubbler?
When used as an Electrolyzer, the jar is filled with distilled water and electrolyte added, the so called bubbler control should be shut off completely (screwed right in) and 12 volts applied to the terminals. Now you should see gas forming in the jar and if you put the end of the tubing into a jar of water you will see bubbles forming at the end of the tubing, if you have no leaks in the W4G cell. This is proof that your electrolyzer is working and putting out hydrogen.
Now if you put this Cell under the hood of your vehicle, how do you know for sure that hydrogen is being forced out the tube into the air intake of your vehicle? You don't ! This where you need a bubbler to visually see the bubbles going out of your electrolyzer. A bubbler is a piece of clear tubing partially filled (3/4 is fine) with water (tap water will do) with the outlet of the electrolyzer going to the bottom of this tube and from the top of this Bubbler is the tubing that goes into your air intake. The main purpose of this Bubbler is to scrub any impurities out of the hydrogen gas and act as Flash Back prevention device if the hydrogen ignited accidentally due to backfiring of the engine, etc. The theory is that the burning hydrogen will be stopped at the bubbler and prevent the electrolyzer from exploding. Hopefully I have explained clearly as to what a Bubbler really is in the creating of hydrogen on demand.
The above video shows the Electrolyzer output tubing going to the bottom of the Bubbler, where the hydrogen gas is forced into the water of the Bubbler and then out the top of the Bubbler into the jar of water at the left where you can see the gas bubbling from the end of the tubing. This bubbler is for illustration purposes only as it is only 1/2 inch in diameter..... should make a bubbler out of at least 1 inch diameter tubing.
When used as a Vaporizer the jar should be filled with water only, no electrolyte and the 12 volt power disconnected either by a switch or removing the electrolyzer fuse. Start the engine and open the so called Bubbler control a few turns to see if bubbles are forming at the bottom of the cell. If you can not get bubbles to form, you do not have sufficient vacuum and will have to move the output tubing from the Air intake to the intake manifold or to any place where there is sufficient vacuum to make the bubbles appear, such as at the PCV valve. Once you have bubbles appearing, then you can adjust the bubbler control for the amount of water vapor you wish to inject into you engine.
As for myself, I made a Vaporizer with only an output, and the bubbler control with tubing to the bottom of the jar, in the cap. This is adjusted for a continuous stream of bubbles, not too much wild bubbling going on. It is connected to the PCV by teeing into the line and my Electrolyzer is connected to the air intake after the MAF sensor.