corner install venting clearance question

[davegod75]

Hi there. Looking at a Harman XXV and have a question on venting. It says the clearance to an inside corner is 12" Does that mean to the center of the vent pipe or to edge of the wall thimble?

 

[bogieb]

Although the install manual is not as clear as it could be, the fact that some lines specify "to the center point" and other lines do not make that distinction, that they mean to the closest edge of the pipe unless otherwise stated.