Our portable air conditioners come with their own specific exhaust hose (1.20 m length).
Extending the hose is not allowed since the appliance performances would be affected and heavily reduced. Extensions also increase the likeability of internal overheating risks and permanent damage to the appliance.
The length of the provided exhaust hose is specifically conceived to let the portable air conditioner operate at its best, safely and without any performance drop.
That explains why venting the unit through a chimney should be avoided; a chimney flue would be an extension to the original exhaust hose and potentially cause it to malfunction or overheat.
