Pellet Venting Size Guide: 3” vs 4”

Question: What is the difference between 3” and 4” pellet venting? Do I need the 3 inch or 4 inch piping? Do I need a fresh air intake? 

Answer: The difference between the two is in how much resistance the exhaust air will have to push through. 4 inch piping has more space and so there is less resistance; especially at elbows/bends. 3 inch is normally sufficient, however if you have longer total venting runs, or more than just a couple bends/elbows, it is likely you will need to use a 4 inch pellet venting system.

If you are in a manufactured home or exceeding 4000ft above sea level, you’ll likely need a fresh air intake as well.

You can check pg. 12-13 of the manual for more specific information regarding exhaust venting and Equivalent Vent Lengths (EVL).