As you enter real data into the sheet, most of those extraneous codes will disappear. I only added data to check the error code equations. You can delete all that. Just don't delete the equations. I have locked the equations but did not protect the sheet. I left that for you to do if you want.

To explain, in line 42, I just had two identical codes for Perph Codes 2 and 3 to check for #9: Same error code. But since I only entered that, it also violates #5 (Code 2, no Code 1), #6 (Code 3, no Code 1 or Code 2), #8 (Code, no hours), and #10 (Same code and hours 2x).