The amount of current passed through the water of an electrode boiler depends on which factor?

The amount of current passed through the water of an electrode boiler is influenced by the depth of the electrodes in the water. When electrodes are submerged to a greater depth, a larger surface area is in contact with the water, which can effectively conduct electricity. This contact helps to establish a higher conductivity path through the water, thereby allowing more current to flow.

In essence, the current in an electrode boiler is proportional to the area of the electrodes that is submerged and how well the water can conduct electricity, which is directly influenced by the depth of those electrodes. A deeper immersion generally enhances the efficiency of heat generation due to increased electrical contact with the water.

The other factors listed, while they may affect other aspects of boiler operation, do not have a direct relationship with the current flowing through the water in the same manner that electrode depth does.