A wind turbine has a wind turbine gearbox, a generator and/or a converter arranged inside a nacelle of the wind turbine. The wind turbine further has a liquid cooler arranged to cool a liquid flowing through the wind turbine gearbox, the generator and/or the converter by way of air ambient to the nacelle. The liquid cooler includes a first liquid cooler part having a first part cooling capacity and a second liquid cooler part having a second part cooling capacity, wherein the second part cooling capacity is greater than the first part cooling capacity. The liquid cooler also includes a bypass conduit arranged to guide a liquid from the first liquid cooler part past the second liquid cooler part, and valve means arranged to control flow through the bypass conduit, wherein the valve means are controlled based on at least one characteristic of the liquid flowing through the liquid cooler. A method for cooling a liquid is also provided.

A method of controlling a wind turbine is provided including at least one fan-cooled unit with a fan adapted to circulate air inside a housing of the fan-cooled unit, which method includes operating the fan-cooled unit in a dryout mode by: disabling a thermal energy reduction the fan-cooled unit, which thermal energy reduction means is adapted to reduce thermal energy of air inside the housing during a normal operation mode of the fan-cooled unit; actuating a fan of the fan-cooled unit to circulate the quantity of air contained in the housing; and monitoring a climate parameter until a target climate condition has been reached. A wind turbine configured to execute the steps of the inventive method is also provided.