The electric heater, in particular, for additional heating of motor vehicles comprises a control unit with power transistors (19) and attached cooling elements (20) which are formed by a cooler body (25) and a heat conductor (24) inserted into the circuit ...

Method for operating the cooling and heating circuit (10) of a motor vehicle that comprises three coolant paths (28, 30, 32) that pass through a bypass line, main combustion engine cooler and heat exchanger respectively. Pump (14), values and control unit ...

A vehicle air conditioning system, especially using carbon dioxide, has a cooling medium circuit comprising a compressor (6), cooler (7), heat exchanger (8), expansion valve (9) and vaporizer (5). To switch from heating to cooling an additional heat exchan...

The circuit has a radiator (2), at least one mechanically driven coolant pump (3) and at least one electrically driven pump (4) for a cooling circuit with a coolant feed (8) and heat exchanger (7) and a heating circuit with a coolant return (9') and heat e...

The system has a first coolant circuit including engine cooling channels and a second coolant circuit for interior heating. Each circuit has at least one line, pump and heat exchanger. The second coolant circuit is connected to the first via feed and outle...