The team provided an update on Andersen's status Monday afternoon after revealing earlier in the day that he was being "evaluated for a medical condition."
Carolina general manager Don Waddell said in a statement that the blood clotting was discovered during recent medical test and will need to be addressed, but the club is "confident that Freddie will be able to make a full recovery." There is no timeline for Andersen's return to the lineup.
Andersen, 34, missed time in October after taking a shot off the mask against the San Jose Sharks. He is in the first season of a two-year, $6.8 million contract he signed as a free agent last summer to stay in Carolina. Andersen is 4-1-0 on the year, with a 2.87 GAA and .897 SV%.
The Hurricanes also announced Monday they signed veteran goaltender Jaroslav Halak to a professional tryout. Halak appeared in 25 games last season for the New York Rangers with a 2.72 GAA and .902 SV% as backup to Igor Shesterkin.
Halak will potentially work in tandem with veteran Antti Raanta. Carolina also has the option to recall top goaltending prospect Pytor Kochetkov from the minors.
Raanta, who signed a one-year deal in the offseason to remain with the Hurricanes for a third season, has struggled. The 34-year-old is 3-1-0 with 3.03 GAA and .870 SV%.
Kotchetkov appeared in three NHL games this year and was 0-3-0 with a 4.33 GAA and .836 SV%, but those numbers have improved in his tenure with the American Hockey League's Syracuse Crunch (3-0-0, 1.63 GAA, .932 SV%).
Carolina faces the Buffalo Sabres on Tuesday.