In the cold winter months, it is the Ford heater hose that provides the warmth your passenger compartment needs for the occupants to stay warm. The heater hoses on your Ford are the polymer components on your car or truck through which the coolant travels from the radiator to your heater core so heat can be provided.
The similarity of the Ford heater hoses and a garden hosed is just in appearance only. The inside of the heater hoses on your vehicle have more reinforcement in the walls and are thicker. Many of them on the newer model Fords are also pre-shaped so they can follow the contours around the engine and not be rubbing up against it. This rubbing can cause a leak over time and should be prevented if possible.
If there is no place where the heater hose is rubbing up against any hot metal components of the engine, the most likely places for a leak to occur is similar to the radiator hoses. This is at the connection to metal outlet or inlet pipes. Since the metal portal on the radiator is very hot, the section of the hose that is just beyond the connection has to endure this heat high level for long periods of time. This causes the polymer to weaken and thin out over time. It is best described as the ballooning of the heater hose. This is when the circumference of the hose increases which decreases the thickness of the hose's wall and is why this area has a tendency to leak coolant.
If you suspect you have a leaking hose in your heater system, checking it with your Ford engine running and the heater on is recommended. If the heater is not on, there will be no flow through this system.