Hi,
In the integrated documentation you can find the different format types.
Format : The way you want to display the symbol (basically you will have %i which will display the currency code next to the price, %n which will display the currency symbol next to it, and %ni which will display both). For more information, you can look at
www.php.net/manual/en/function.money-format.php
So to use the symbol instead of the code, you have to set the format %n in the settings of your currency via the menu System > Currencies.