When the unit is running and it is very cold water seeps from the duct attached to thefurnance at the seem of the duct going away from the furnace. Is this condenstation.
A humifiier is attached to this unit and the unit is only 1.5 years old.

The water might be from the humidifier. Humidifiers have to be serviced every year to prevent build up of calcium and water stone. The build up can misdirect the water flow over the pad and cause a leak. Looks like it is time to service your humidifier.