Hey I hope you guys can help my dealer is clueless.  I bought a harman accentra from my local fireplace dealership along with the zc box and vent pipe.  When I tried to install the 4 inch L vent pipe that he supplied it would not fit through the hole.  The hole on the zc measures 4 1/2 while the L pipe measures 4 and 3/4.  Did the dealer give me the wrong pipe?  I read that L and pl are interchangeable but maybe the dimensions are just slightly different?  Do I need to return the pipe?
	
		
			
		
		
	
				
			 
	 
	 
 
		 
 
		 
 
		 
 
		