A wood material board hot-pressing device with (a) a primary circuit, with - a primary circulation pump, - a supply pipe for the discharging of hot heat transfer fluid from a heat generator and - a return pipe for the supplying of cooled heat transfer fluid to the heat generator, (b) a secondary circuit, with - a pressing device for pressing wood material boards, - a supply channel for the supplying of heat transfer fluid to the pressing device and - a return channel for the returning of cooled heat transfer fluid to the primary circuit, and (c) a controlling device, which - comprises a control valve and - is set up to regulate a flow of heat transfer fluid from the primary circuit to the secondary circuit, characterised by (d) a variable output secondary circulation pump, which is set up to circulate the heat transfer fluid in the secondary circuit, and/or the control valve being a two-way control valve which includes a position indicator, (e) wherein the controlling device (i) features a heat output recording device, with - an inlet temperature gauge to measure an inlet temperature (T 34) of the heat transfer fluid, which flows in the secondary circuit to the pressing device, and - a return temperature gauge to measure the return temperature (T 38) of the heat transfer agent, which flows back in the secondary circuit from the pressing device. and (ii) is set up to automatically regulate a heat output, sent to the pressing device, by reference to the volumetric flow ( V̇) of heat transfer fluid through the secondary circuit and a temperature difference (Δ T 14) between inlet temperature (T 34) and return temperature (T 38) in the secondary circuit. (a) a primary circuit, with - a primary circulation pump, - a supply pipe for the discharging of hot heat transfer fluid from a heat generator and - a return pipe for the supplying of cooled heat transfer fluid to the heat generator, - a primary circulation pump, - a supply pipe for the discharging of hot heat transfer fluid from a heat generator and - a return pipe for the supplying of cooled heat transfer fluid to the heat generator, (b) a secondary circuit, with - a pressing device for pressing wood material boards, - a supply channel for the supplying of heat transfer fluid to the pressing device and - a return channel for the returning of cooled heat transfer fluid to the primary circuit, and - a pressing device for pressing wood material boards, - a supply channel for the supplying of heat transfer fluid to the pressing device and - a return channel for the returning of cooled heat transfer fluid to the primary circuit, and (c) a controlling device, which - comprises a control valve and - is set up to regulate a flow of heat transfer fluid from the primary circuit to the secondary circuit, - comprises a control valve and - is set up to regulate a flow of heat transfer fluid from the primary circuit to the secondary circuit, (d) a variable output secondary circulation pump, which is set up to circulate the heat transfer fluid in the secondary circuit, and/or the control valve being a two-way control valve which includes a position indicator, (e) wherein the controlling device (i) features a heat output recording device, with - an inlet temperature gauge to measure an inlet temperature (T 34) of the heat transfer fluid, which flows in the secondary circuit to the pressing device, and - a return temperature gauge to measure the return temperature (T 38) of the heat transfer agent, which flows back in the secondary circuit from the pressing device. and (ii) is set up to automatically regulate a heat output, sent to the pressing device, by reference to the volumetric flow ( V̇) of heat transfer fluid through the secondary circuit and a temperature difference (Δ T 14) between inlet temperature (T 34) and return temperature (T 38) in the secondary circuit. (i) features a heat output recording device, with - an inlet temperature gauge to measure an inlet temperature (T 34) of the heat transfer fluid, which flows in the secondary circuit to the pressing device, and - a return temperature gauge to measure the return temperature (T 38) of the heat transfer agent, which flows back in the secondary circuit from the pressing device. and - an inlet temperature gauge to measure an inlet temperature (T 34) of the heat transfer fluid, which flows in the secondary circuit to the pressing device, and - a return temperature gauge to measure the return temperature (T 38) of the heat transfer agent, which flows back in the secondary circuit from the pressing device. and (ii) is set up to automatically regulate a heat output, sent to the pressing device, by reference to the volumetric flow ( V̇) of heat transfer fluid through the secondary circuit and a temperature difference (Δ T 14) between inlet temperature (T 34) and return temperature (T 38) in the secondary circuit.