A washing and drying laundry appliance comprising: a rotating drum for receiving items to be processed; an airflow path that selectively directs a flow of process air across a first heat exchanger in a drying condition and a washing condition, wherein the drying condition is defined by the process air being directed through the rotating drum and through a third heat exchanger, and the washing condition is defined by the process air being directed to the rotating drum rather than to the third heat exchanger, so that the process air is directed away from the third heat exchanger; a fluid path that selectively directs fluid through a second heat exchanger in the washing condition, wherein the washing condition is further defined by the fluid being selectively directed to the rotating drum; and a heat exchange circuit that further defines the drying and washing conditions (30, 32), the washing condition defined by the first heat exchanger being a cooling module for the process air and the second heat exchanger being a heater for the fluid; and characterized in that, said heat exchange circuit being a reversible heat exchange circuit, the drying condition defined by the first heat exchanger being a heater for the process air and the second heat exchanger being a cooling module for the fluid; said fluid path selectively directs fluid through a second heat exchanger in the drying condition, the drying condition being further defined by the fluid being selectively directed through the third heat exchanger to intersect with the process air, the third heat exchanger in the drying condition defining a filtration and moisture condensation mechanism for removing moisture and particulate matter from the process air within the third heat exchanger, and further comprising a control in communication with the reversible heat exchange circuit, wherein the control is also in communication with a fluid diverter valve of the fluid path and an air diverting system of the airflow path to selectively and alternatively define the washing and drying conditions (32, 30) in each of the reversible heat exchange circuit, the fluid path and the airflow path. a rotating drum for receiving items to be processed; an airflow path that selectively directs a flow of process air across a first heat exchanger in a drying condition and a washing condition, wherein the drying condition is defined by the process air being directed through the rotating drum and through a third heat exchanger, and the washing condition is defined by the process air being directed to the rotating drum rather than to the third heat exchanger, so that the process air is directed away from the third heat exchanger; a fluid path that selectively directs fluid through a second heat exchanger in the washing condition, wherein the washing condition is further defined by the fluid being selectively directed to the rotating drum; and a heat exchange circuit that further defines the drying and washing conditions (30, 32), the washing condition defined by the first heat exchanger being a cooling module for the process air and the second heat exchanger being a heater for the fluid; and characterized in that, said heat exchange circuit being a reversible heat exchange circuit, the drying condition defined by the first heat exchanger being a heater for the process air and the second heat exchanger being a cooling module for the fluid; said fluid path selectively directs fluid through a second heat exchanger in the drying condition, the drying condition being further defined by the fluid being selectively directed through the third heat exchanger to intersect with the process air, the third heat exchanger in the drying condition defining a filtration and moisture condensation mechanism for removing moisture and particulate matter from the process air within the third heat exchanger, and further comprising a control in communication with the reversible heat exchange circuit, wherein the control is also in communication with a fluid diverter valve of the fluid path and an air diverting system of the airflow path to selectively and alternatively define the washing and drying conditions (32, 30) in each of the reversible heat exchange circuit, the fluid path and the airflow path.