Upon arrival performed furnace tune up on 2014 unit. Replaced filter was a 20x25x1. Customer was saying downstairs does not get hot and some areas no air flow. Inspected duct work and was the original duct work of the home. Did not have dampers to adjust air flow. Ducts are breached and not sealed. Also improper sizing of ducts. Cycled system on and off. System is operational upon departure.