A hydraulic heating and/or cooling system hydraulic manifold is constructed in a modular manner with a main module (2). At least one load module (4) is connectable to the main module (2) and includes a hydraulic connection (22, 24) for a load circuit, and a closed-loop control device (26, 28) controlling flow through the load and for connection to an identically configured further load module (4). The at least one load module (4) includes a circuit board (44) which extends between a first (34) and a second axial end (36) of the load module (4) and which at its first (34) and second end (36) have electrical couplings (50, 52) which correspond to one another. The electrical coupling (52) at the second end (36) of the circuit board (44) can electrically conductively engage with an electrical coupling (50) at the first end (34) of the further identical load module (4).