Other than the moves Flame Wheel, Sacred Fire, Flare Blitz, Fusion Flare, Scald, and Steam Eruption, a damage dealing Fire type move only thaws a frozen Pokemon if it used against the Pokemon, not by it.
For example, if a frozen Pokemon is hit by Flamethrower by an opponent or teammate, it will be thawed, but it cannot thaw itself with Flamethrower.
Source