You simply cannot buy a better tankless water heater. Each of the tankless water heaters on our shortlist is a top choice in its price/performance bracket. However, the overall winner of our âBest of the Bestâ award is definitely the Stiebel Eltron Tempra 24 Plus.
The difference between the lux and the lumen is that the lux takes into account the area over which the luminous flux is spread. 1000 lumens, concentrated into an area of one square metre, lights up that square metre with an illuminance of 1000 lux.
Lumen is the SI unit of the luminous flux, which is a measure of the total amount of visible light emitted by a source. It is the perceived power of the light from a source.umen and Lux are two photometric units in the SI system of units. They are closely related to each other and, in simple language, measure how bright a light source appears in two different contexts. These measurements are important in light sources and other cases where the intensity of the light plays a role.