Arrangement and operating method in a refrigerant circuit

The arrangement has at least one gas cooler/condenser (5), an evaporator (10), an expansion valve (9) and a compressor (3), whereby the coolant is subjected to heat exchange with the cooling liquid (14) of the motor vehicle engine at one or more points in the coolant circuit. The compressor is thermally connected to or combined with at least one coolant/ cooling liquid heat exchanger, whereby there are at least one flow channel for the coolant and at least one flow channel for the coolant liquid. An independent claim is also included for a method of operating an air conditioning system.