It is required to replace the car heater radiator in the presence of the following symptoms: cold air coming from the diffusers when the engine is warm, reduced coolant level, ingress of the coolant inside the passenger compartment and underneath the car, windows covered with steam and an oily film. Before replacing the equipment, the battery terminals are disconnected and the radiator is dismantled from the engine compartment or from the passenger compartment under the front panel (in this case, the dashboard is disassembled). When the radiator can be accessed, the refrigerant is drained, the radiator is removed and a new one is installed.