Wood Pellet Stove 3" venting vs. 4" venting

[Don2222]

Hello

Well, I have read that 4" venting is recommended in long runs and installations way above sea level for better drafting.

The Avalon Astoria has a 4" stove pipe which needs 4" venting even though it is not much different than other stoves. I also have 3" venting for testing other pellet stoves. Now I have had more leakage problems with the 3" venting than the 4" venting. It seems that like a car muffler, there is more back pressure in the 3" venting and that requires much more sealing!

I have seen regular pellet stove installs with either 4" or 3" venting. The 4" installs have a 3" to 4" adapter coming out of the back of the 3" stove's exhaust pipe.

So even though it is more expensive for the 4" venting, it just seems better and not many leakage problems?

Does anyone else have any experience and comments on this?

 

[DexterDay]

My two 3" Pellet Vent Pro systems have no sealant or tape... (on joints other than the Appliance adapter)

My 4" Pellet Vent Pro system for my Fahrenheit does have tape...... (on all joints)

So I have opposite problems.

 

[Don2222]

I should say I have the regular Duravent 3" and 4" so maybe the Pellet Vent Pro pipe is different?

 

[DexterDay]

I should say I have the regular Duravent 3" and 4" so maybe the Pellet Vent Pro pipe is different?

It is different. It is Multi fuel and it has better seals....

 

[mepellet]

You are right about the increased static pressure in a 3" system. Say the exhaust blower is rated for 100 cfm. The static for a clean 3" system sees about 2.4" of w.g. per 100' of venting. The same blower on a 4" system sees about 0.6" of w.g. per 100' of venting. It would be interesting if we could find a fan curve from a stove manufacturer so we could determine the difference in airflow from a 3" venting system and a 4" venting system.

 

[AbetterChimneynm]

Well here at our store for the most part we run three inch venting, unless the run is going to be over 15ft then we do four inch as far as leaks we run icc pipe has a high temp rubber seal inside the pipe and to be honest i feel it is the best pipe out there no sealant needed and no leaks!