l installation on the register of the water meter, and "V" is used for vertical installation.Volumetric water meter can be installed in any position, without affecting the accuracy. TYPES BY WATER TEMPERATUREBy water temperature, water meter inlcudes cold water meter and hot water meter1) Cold water meter: Water temperature between 0~30℃2) Hot water meter: Water temperature between 30~90℃The requirements vary slightly from country to country, with a limit of 50 degrees Celsius for some cold w