Quadrafire Mt. Vernon smoke problem

[sc0872]

My brother has this stove and it is filling his basement with a lot of smoke. What are some things that could cause this. I don't think he has an OAK not sure if stove has one.

 

[tsmith]

Could be a couple of things. clogged exhaust pipe, leaking exhaust pipe joints, bad door gasket. Possibly even maybe the exhaust blower is not working although I believe if that was the case, the stove would shut itself down.

 

[Wood Heat Stoves]

has it always smoked, or is this a new issue?
likely needs a cleaning