RWE AG (RWE)’s halted 1,284-megawatt Gundremmingen B nuclear reactor showed a malfunction in the process of taking it offline, the company said. RWE started to take the reactor offline on May 1 for maintenance but a water draining device failed to work properly during tests, according to the operator’s website. RWE said it categorized the fault at „INES 0“ or the lowest level of seriousness. Gundremmingen is not due to resume power generation until May 24 and May 26, according to data the utility posted on its website. E.ON AG (EOAN) owns a 25 percent stake in the facility.