Yes, conditional formatting works for this.
Do menu command Format/Conditional Formatting, and choose "Cell Value Is" "Equal To" in the drop downs, and type =CHAR(226) for the value, press the Format button and choose a font colour of Red.
Simply add another condition for a Cell Value Is/Equal To/=CHAR(225) for a format of font colour Green, and you're done.
There, easy as that.
Cheers, Glenn.