Humidification Made Simple:
What is an electrode steam humidifier?
An electrode steam humidifier is an isothermal humidifier which generates an flow of electrons in order to heat water.
This technology makes use of electrical resistance, i.e. the water's conductivity. Current flow and in turn the volume of steam generated is determined through the electrodes' surfaces, electrode gaps and their immersion depth. Grid electrodes with a wide surface area are used in order to provide the hardeners in the water with as large a surface area as possible (onto which the hardeners can settle). The hardeners crystallize (harden) onto these electrodes and act as additional insulators. Since the water for vaporization requires an electrode immersion depth which corresponds to current consumption, the water level in the steam cylinder always moves toward the top until the available electrode surface becomes smaller and smaller and in turn the steam output becomes lower and lower. An signal from the humidifier's electronic system indicates when the cylinder is full. Depending on the type of cylinder, a cylinder can either be reused (in the case of cleanable steam cylinders) or exchanged for a new one (disposable concept). The electrodes always remain in the water in order to ensure the unit is always ready for use, even when it is at a stop. The controllable steam output is therefore in the lower range and limited to 10 to 20% of the steam output depending on water quality.
(always adjustable 15–100%)
Steam Humidifier Operation Using Resistance Heating
The heating current is activated via a contactor, through an electrical control impulse. The magnetic inlet valve opens after a delay and allows water (based on the steam output) to flow in from below, over the filling cup and into the steam cylinder. The magnetic inlet and outlet valves are continuously controlled through the control electronics in the unit so the water quality and conductivity in the steam cylinder always remains the same. The technology used here is known as auto-adaptive treatment of the available untreated water.
Schematic layout of a steam humidifier
which uses electrode heating