Help with Sumif function please..

Could someone please help me??
I need to sum the values of a range of cells that contain certain text (product codes) into another cell.
For example a1,a2 and a3 might contain the letters "ahf" with a corresponding amount of $2, $4 and $10 in cells b1, b2 and b3.

Is there a way that I can have excel sum the totals of a given group of product codes into another cell? (sum the total of "ahf" into c3 for instance?).

Any help would be very much appreciated.
Kind regards,
John.S