Princess PE-32, my second year. Stove pipe, blower, stack height, shields, and damper type questions.

[moresnow]

Inspect your cap. It may have a spark arresting screen that is plugging. Very, very common issue with your exact results. Sometimes difficult if not impossible to see from the ground.
May as well sweep the pipe entirely. Clogging/restriction can occur much quicker than one would expect.
Pull the connector pipe off the stove and clean out the stove around the bypass assembly and behind the catalyst.
likely you just need normal maintenance. Good luck.

 

[stoveliker]

I agree with the cap .

A leaking flue may exacerbate buildup because air being sucked in will cool flue gases.