Operating time
It is the operating time of the humidifier with a full tank. It depends on the volume of the tank and on the water consumption (see below for both). For models with humidity control (see "Features"), this parameter can be indicated in different ways: in some cases, the maximum duration of the operation is given (at the minimum output humidity), and in others — vice versa. Nevertheless, according to the declared figures, it is quite possible to estimate the operating time at least approximately.
Water consumption
The rate at which the humidifier uses water. Knowing this speed and the volume of the water tank (see below), you can determine the operating time. Also, this indicator can be used to evaluate the performance and speed of the device: the
higher the water consumption, the more it evaporates into the air per unit of time. Accordingly, a high-consumption device allows you to quickly achieve the desired humidity, all other things being equal.
Note that for models with humidity control (see "Features"), the maximum consumption is most often indicated, at the highest humidity settings. And in evaporate devices(see "Type"), the claimed consumption will be achieved only with dry air (30% or less) — at higher humidity, evaporation will slow down and water consumption will decrease.
Water tank volume
The volume of the water tank installed in the humidifier. Large capacity allows you to work longer without refuelling but affects the dimensions and weight of the device. Therefore, manufacturers choose the volume based on a compromise between these points and taking into account water consumption. Usually, the volume of the tank is chosen in such a way that the humidifier can work quietly on a single refill for at least 2-3 hours, and often even more. Accordingly, the more capacious the tank, the more powerful and performant the device, as a rule. So, models with a volume
of up to 2 litres belong to the entry-level,
from 2 to 4 litres — to the average,
from 4 to 6 litres — to the larger than average category, and in the most capacious devices this figure can
exceed 6 litres .
Note that for models with the possibility of using a bottle (see below), this paragraph often indicates the optimal capacity of the bottle (such devices may not have their tanks).
