Does changing the order total from the admin automatically refund the customer the difference?

If I change the order total on an order to a lower amount, will it automatically refund the customer the difference or will I need to refund them manually through Paypal.

I am using Nopcommerce version 2.65 with Paypal Standard for the payments.

I just want to make sure before I change it.  Thanks!

I looked at a copy of 2.6 and no, it doesn't do anything except change the values on the order.  You will need to refund manually.