I looked at the 82 series manual and it shows the charge pump relief on page 3-37 and says to go to page 2-94 for instructions on checking pressure but there is no page 2-94, section 2 ends at 2-65 I think. You could try the Quietline manual, the procedure should be the same.
https://s3.us-east-2.amazonaws.com/c...ervice+Man.pdf
Go to page 2-92 for pressure check