Abstract: A commissioning module 100 for a fluid distribution system includes a plurality of fluid distribution valves 7, 8, 9, 10, isolating valves, 2, 16, 18, fluid flow-regulating valves 25, 26, 27, 28, flow rate measuring devices and at least one drain-off cock 6. The module 100 is operable to establish and to maintain set fluid-flow conditions in the fluid-distribution system. In operation the fluid distribution valves 7, 8, 9, 10 supply a working fluid to heat exchangers via supply lines 11, 12, 13, 14 and the working fluid returns from the heat exhangers by way of fluid exhaust lines 31, 32, 33, 34. The module 100 permits the filling and pressure testing of a fluid distribution system to which it belongs by use of a test point 15 for monitoring the fluid supply pressure and a test point 20 for monitoring the fluid exhaust pressure.