A heating or cooling system, in particular domestic, comprising: a heat or cold generator connectable in a heat exchange relationship to a hydraulic heating and/or cooling circuit, a circulation pump, connectable to the hydraulic circuit, to convey a flow of water into the hydraulic circuit, an electronic control system in signal connection with the heat or cold generator and with the circulation pump, to control the operation of the heat or cold generator and the circulation pump, characterized by comprising: an air detection module (7, 7') configured so as to perform an air detection process, comprising one or more air detection steps (15.1,..., 15.n), wherein: - with the circulation pump activated at a circulation speed, it detects a parameter (x) indicative of the flow rate of the water inside the hydraulic circuit, - it collects a plurality of values (x_t) of the parameter (x) detected in a detection time interval, - it calculates a variation (FlowRate_StdDev) of the plurality of values (x_t) collected in the detection time interval, - it compares the calculated variation (FlowRate_StdDev) with a variation threshold value (Threshold_var) and: if the calculated variation (FlowRate_StdDev) is greater than the variation threshold value (Threshold_var), it generates a notification signal of air presence in the hydraulic circuit, and if the calculated variation (FlowRate_StdDev) is lower than the variation threshold value (Threshold_var), it does not generate the notification signal of air presence in the hydraulic circuit. a heat or cold generator connectable in a heat exchange relationship to a hydraulic heating and/or cooling circuit, a circulation pump, connectable to the hydraulic circuit, to convey a flow of water into the hydraulic circuit, an electronic control system in signal connection with the heat or cold generator and with the circulation pump, to control the operation of the heat or cold generator and the circulation pump, characterized by comprising: an air detection module (7, 7') configured so as to perform an air detection process, comprising one or more air detection steps (15.1,..., 15.n), wherein: - with the circulation pump activated at a circulation speed, it detects a parameter (x) indicative of the flow rate of the water inside the hydraulic circuit, - it collects a plurality of values (x_t) of the parameter (x) detected in a detection time interval, - it calculates a variation (FlowRate_StdDev) of the plurality of values (x_t) collected in the detection time interval, - it compares the calculated variation (FlowRate_StdDev) with a variation threshold value (Threshold_var) and: if the calculated variation (FlowRate_StdDev) is greater than the variation threshold value (Threshold_var), it generates a notification signal of air presence in the hydraulic circuit, and if the calculated variation (FlowRate_StdDev) is lower than the variation threshold value (Threshold_var), it does not generate the notification signal of air presence in the hydraulic circuit. an air detection module (7, 7') configured so as to perform an air detection process, comprising one or more air detection steps (15.1,..., 15.n), wherein: - with the circulation pump activated at a circulation speed, it detects a parameter (x) indicative of the flow rate of the water inside the hydraulic circuit, - it collects a plurality of values (x_t) of the parameter (x) detected in a detection time interval, - it calculates a variation (FlowRate_StdDev) of the plurality of values (x_t) collected in the detection time interval, - it compares the calculated variation (FlowRate_StdDev) with a variation threshold value (Threshold_var) and: - with the circulation pump activated at a circulation speed, it detects a parameter (x) indicative of the flow rate of the water inside the hydraulic circuit, - it collects a plurality of values (x_t) of the parameter (x) detected in a detection time interval, - it calculates a variation (FlowRate_StdDev) of the plurality of values (x_t) collected in the detection time interval, - it compares the calculated variation (FlowRate_StdDev) with a variation threshold value (Threshold_var) and: if the calculated variation (FlowRate_StdDev) is greater than the variation threshold value (Threshold_var), it generates a notification signal of air presence in the hydraulic circuit, and if the calculated variation (FlowRate_StdDev) is lower than the variation threshold value (Threshold_var), it does not generate the notification signal of air presence in the hydraulic circuit.