Sometimes there can be too much resistance in the machine through the chimney causing these smoke leaks.
May I know how the chimney is constructed, if it has an intermediate filter, how many bends are in the chimney, etc.?
If the chimney is too long and with too many bends, smoke may leak through the cooling tray, as the smoke will seek the quickest exit.
We usually see these things due to a blockage somewhere or another machine that are connected to the chimney.
How often do you clean the chimney duct?
Have you ever perform the cleaning guide? If not, please do so and let me know if after the cleaning the smoke leak has disappeared.
