Got my new Harman Accentra Insert installed. Been getting a mild smokey smell on most occasions. Had Dealer come and replace the Combustion Motor, which had died. Yesterday I thought it was great. Could barely smell anything. Today, its been back to the same. You can get a stronger smell from the gap between the surround and the Fireplace. I'm sure the pipe is sealed well. BUT, going by the dealers OK, I only installed the standard 5 feet Flex from the stove to just into the Liner and packed the damper area with insulation. My Chimney from the stove is about 24 feet to the top and 10*12 Liner. I have a Top Mounted Damper which is open. Is it more likely that the smoke is not able to rise that far in the chimney and is coming back down into the fireplace. should I stop being cheap and get someone in to put pellet pipe to the top.