This operation will take 72 days.

Cold phase includes hydraulic tests to verify tightness and strength of reactor plant components,  circulation flushing of  the primary and secondary circuits, their water chemistry adjustment, verification of design values of thermohydraulic, strength, vibration, dynamic characteristics of the reactor plant and of the primary circuit equipment.

As for the hot run, this is performed in order to confirm operability of the main and auxiliary equipment and reactor plant systems when they are already in the design, operating modes. During this sub-phase experts shall run the four reactor coolant pump sets for 100 hours at hot parameters (temperature of +260°С minimum), blow down main steam lines with their own steam, conduct safety systems integrated tests, check the auxiliary power supply system, reactor plant control and protection systems.

Vladimir Pereguda, Leningrad NPP director:

- We have come to the power unit commissioning phase. According to the Russian and international NPP safety norms and rules it is required to verify high quality of installation operations applied when erecting the equipment and process systems, and confirm that the Power Unit will be operating in full compliance with the design. For this end, more than one hundred of pre-start tests are to be performed during the cold and hot run for the reactor plant equipment and systems.

(material provided by the Information and PR Department of the Leningrad NPP)