Patent ID: 7069976

Claim:
A procedure for controlling the temperature of at least one outbound secondary flow ( 2 u ) in a secondary circuit from a heat exchanger ( 1 ) by means of a primary flow ( 3 ) in a primary circuit, where a control unit ( 7 ) controls a regulatory member ( 5 , 11 ) that regulates the primary flow, wherein the temperature T sec — in of the inbound secondary flow ( 2 i ) in the secondary circuit is known or measured, characterised in that, a) a parameter array, characteristic of the enthalpy difference (Δh) between the inbound primary flow ( 3 i ) to the heat exchanger ( 1 ) and the outbound primary flow ( 3 u ) from the heat exchanger ( 1 ), is determined, b) a parameter array, characteristic of the mass flow (m sec ) in the secondary circuit ( 2 ), is determined, c) a parameter array, characteristic of the mass flow (m prim ) in the primary circuit ( 3 ), is determined, d) and that the parameters determined in points a) through c) are transmitted to the control unit ( 7 ) for controlling the regulatory member ( 5 , 11 ), wherein the primary flow ( 3 ) is controlled in dependence of the secondary flow ( 2 ), so that the power transferred between the heat exchanger and the primary flow ( 3 ) substantially corresponds to the sum of: 1) the power needed to change the temperature of the secondary medium from the current inbound temperature T sec — in to the desired outbound temperature T sec — out — set point and 2) assumed power demand for compensation of stored energy in the heat exchanger ( 1 ), and 3) assumed leak power from the heat exchanger.