A method for producing direct reduced iron (DRI), comprising the steps of: controlling a flow rate of a non-heated hydrogen gas into a cooling section (5) such that Tdriout<Tdrioutmax, wherein Tdrimax is a set maximum allowable temperature of the DRI exiting the cooling section (5), measuring temperature of cooling gas Tcooltop leaving the cooling section and increasing the flow rate of the cooling gas, FRcoolgas, introduced into the cooling section (5) until Tcooltop=Tcooltopmin, adjusting a flow rate of a separately heated reduction gas introduced into a reduction section (4) and measuring the degree of metallization of the produced DRI and measuring the top gas temperature Ttopgas, and determining a minimum top gas temperature, Ttopgasmin, below which the degree of metallization is below a minimum allowable value, and measuring the top gas temperature Ttopgas and controlling at least one of the flow rate of the heated reducing gas and the temperature Tredgas to which the heated reducing gas is heated such that TtopgasminTtopgasTopgasmax, wherein Topgasmax is a set maximum allowable temperature of the top gas.