This is my code - and I get the wrong output.... shouldnt it be around 900 K something?

restart:with(Units[Standard]):
T:=1200*Unit('degF');convert(T,'units','K');Units[UseSystem]('SI'):
evalf(%);
                    1200 Units:-Unit('degF')
                     2000                 
                     ---- Units:-Unit('K')
                      3                   
                  666.6666667 Units:-Unit('K')
T:=1200*Unit('Fahrenheit');convert(T,'units','K');Units...