Was here for a furnace cleaning. Performed a furnace cleaning. Cleaned the burners and the flame sensor sensor. Checked the furnace heat exchanger. Wiped down the inside of the furnace. Checked the furnace electrical. Cycled the furnace. Performed a furnace combustion test. The furnace is running at this time. The furnace is 16 years old. The average life expectancy of a furnace is 15 years. Recommend replacing the furnace due to the age of the furnace. During the cleaning. Found that the transition assembly is cracked along the bottom and is leaking water in the furnace. The customer has a home warranty and will be submitting a claim.