Metering valve assembly and method for operating a metering valve assembly

摘要

A metering valve assembly having a metering valve for metering an aqueous urea solution for posttreatment of exhaust gases from internal combustion engines, the liquid being capable of being fed in a feeding direction to the metering valve and a mixing chamber being provided, in which the liquid is miscible with a gas in a gas flow. The metering valve is evacuatable contrary to the feeding direction.