Scald half and half over medium heat in a medium sauce pan. Remove from heat.
In a stand mixer whisk together the yolks and sugar until light and fluffy, then gradually pour the scalded half and half down the side of the bowl as the mixer is still going.
Pour the mixture back into the sauce pan, stirring constantly with a wooden spoon until the mixture has thickened and will coat the back of the spoon. Remove from heat, and pour through a fine mesh sieve into a clean bowl. Add in orange water and chill the custard thoroughly over an ice bath. Let sit about half an hour.
Transfer the mixture to an ice cream maker. Allow the ice cream to churn until finished, and freeze according to the manufacturer's instructions.