Which hose is input and out on heatercore?

In a typical heater core setup, the input hose is the one connected to the engine's coolant outlet, bringing hot coolant into the heater core. The output hose returns the cooled coolant back to the engine or the coolant reservoir. It's important to ensure that these hoses are correctly connected to maintain proper heating function in the vehicle's cabin. Always refer to the specific vehicle's service manual for precise hose identification.