The defect was appear to be on a small bore section of pipe upstream of a steam trap on a socket weld that resulted in a minute steam leak on the upstream side of a main steam isolation valve.
FPL said that it needed to reduce temperature to less than 200 degrees F to depressurize the steam line, to fix the problem.
While bringing the unit to Mode 3, a main steam isolation valve failed to close.
The company declared the valve inoperable due to its inability to fulfill a safety function. That failure required the company to put the unit in Mode 3 in six hours and Mode 4 within the following six hours. Within an hour, however, the main steam isolation valve closed.
FPL did not say when the unit would try to restart again, noting it was examining the cause of the main steam isolation valve failure.
The unit was shut for the refueling on March 16, 2009.
The unit’s last shut for refueling from about September 2, 2007 to October 17, 2007 and is on an 18-month refueling cycle.
The 2,196 MW Turkey Point station is located in Florida City in Miami-Dade County, about 25 miles south of Miami.
The station are various units: the 398 MW oil/natural gas-fired unit 1, the 400 MW oil/gas-fired unit 2, two 693 MW nuclear units, 3 and 4, the 1,150 MW combined-cycle gas-fired unit 5, and a handful of 2 MW and 3 MW oil-fired turbines.
The unit 1 has entered service in 1967, unit 2 in 1968, unit 3 in 1972, unit 4 in 1973 and unit 5 in 2007.
Unit 4 at the station continued to operate at full power.
One MW powers around 300 homes in Florida.
The U.S. Nuclear Regulatory Commission renewed the plant’s original 40-year operating licenses in 2002, for both units for additional 20 years until 2036 and 2043.
The company plans to spend around $1.5 billion to increase about 400 MW of capacity to the company’s existing Saint Lucie and Turkey Point reactors by 2012.
