The Chimney Sweep

Hello, I am a newbie . I recently purchased a Harman P43 pellet stove from a Harman dealer (whom I would not ever recommend). I have a few questions hoping someone can answer.
My outside air intake hose is just shoved into the back of my pellet stove, I can move it...it that ok? Or will that draw more cold in air in as I noticed the stove is running a lot. The outside vent and intake are also on the same thimble plate does that make a difference?
Thank you all for your advise, it is very much appreciated!!

I own a Harman 2.6 tl wood burning stove. My chimney is outside and the internal stovepipe is insulated. Im having an issue with smoke occasionally being puffed back into the house through the front door. I recently replaced the gaskets in the front door and the top load door. This usually happens with the primary draft closed and the lower draft set at 2 notches to from the right almost max. air but not quite max. Usually just before the smoke goes through the door gasket you can hear a howling of the fire in the chamber. This also occurs long after the fire has been started, not on start up
Bill

Hello, I have been burning wood for 40 years and I’m switching to coal because I can’t huff wood around any more. I have an existing 8 inch triple wall chimney that goes straight up thru the roof, can I run a 6 inch pipe thru this to vent my coal stove. Thanks