Yes, CONVERTED is a Scrabble word!

Letter values in Scrabble US: C 3, O 1, N 1, V 4, E 1, R 1, T 1, E 1, D 2.

Is it a valid word?

CONVERTED is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

change from one system to another or to a new plan or policy
change the nature, purpose, or function of something
change religious beliefs, or adopt a religious belief
exchange or replace with another, usually of the same kind or category
cause to adopt a new or different faith
score an extra point or points after touchdown by kicking the ball through the uprights or advancing the ball into the end zone
complete successfully
score (a spare)
make (someone) agree, understand, or realize the truth or validity of something
exchange a penalty for a less severe one
change in nature, purpose, or function; undergo a chemical change

Also: change over, win over, born-again.