Point Lepreau began sending energy to the grid on Monday with the reactor currently at 35 per cent power.
In a release, NB Power says fuelling will resume in the coming week.
President Gaetan Thomas says the issues they have been managing in their first five months of operation are normal with a restart following a refurbishment.
Thomas says NB Power customers can be assured that the period of low production at Lepreau does not diminish the total lifetime output expected from the plant.