An assembly for frothing a fluid including: - a fluid reservoir for holding fluid to be frothed, - a controllable air source assembly including an air channel having an air inlet and a downstream end; - a fluid channel extending from a fluid inlet to a fluid outlet, the fluid channel including subsequently: ~ an air inlet emanation point to which the downstream end of the air channel is connected; ~ a pump; ~ a heater; ~ a valve assembly having a first state in which fluid is channeled to the fluid outlet of the fluid channel and a second state in which the fluid is diverted from the fluid channel to a second fluid outlet of the valve assembly; the assembly additionally including: - a water supply channel connected to the fluid channel and including a controllable water valve; - a cleaning reservoir; - a return channel having an upstream end that is connected to the second fluid outlet of the valve assembly and having a downstream end that emanates in the cleaning reservoir; and - an electronic controller assembly configured to control at least the pump, the heater, and the valve assembly, wherein the electronic controller assembly is configured to operate the assembly in a production mode and in a cleaning mode; wherein, in the production mode, the fluid inlet is inserted in or at least connected to the fluid reservoir, such that, during the production mode, fluid to be frothed is supplied to the fluid channel due to the fact that the fluid inlet of the fluid channel is supplied with fluid to be frothed; characterized in that the fluid channel further comprises a fluid restriction, and in that in the cleaning mode, the fluid reservoir and the fluid inlet are disconnected, and in that, during at least part of the cleaning mode, the fluid inlet of the fluid channel is supplied with cleaning fluid. - a fluid reservoir for holding fluid to be frothed, - a controllable air source assembly including an air channel having an air inlet and a downstream end; - a fluid channel extending from a fluid inlet to a fluid outlet, the fluid channel including subsequently: ~ an air inlet emanation point to which the downstream end of the air channel is connected; ~ a pump; ~ a heater; ~ a valve assembly having a first state in which fluid is channeled to the fluid outlet of the fluid channel and a second state in which the fluid is diverted from the fluid channel to a second fluid outlet of the valve assembly; ~ an air inlet emanation point to which the downstream end of the air channel is connected; ~ a pump; ~ a heater; ~ a valve assembly having a first state in which fluid is channeled to the fluid outlet of the fluid channel and a second state in which the fluid is diverted from the fluid channel to a second fluid outlet of the valve assembly; the assembly additionally including: - a water supply channel connected to the fluid channel and including a controllable water valve; - a cleaning reservoir; - a return channel having an upstream end that is connected to the second fluid outlet of the valve assembly and having a downstream end that emanates in the cleaning reservoir; and - an electronic controller assembly configured to control at least the pump, the heater, and the valve assembly, wherein the electronic controller assembly is configured to operate the assembly in a production mode and in a cleaning mode; - a water supply channel connected to the fluid channel and including a controllable water valve; - a cleaning reservoir; - a return channel having an upstream end that is connected to the second fluid outlet of the valve assembly and having a downstream end that emanates in the cleaning reservoir; and - an electronic controller assembly configured to control at least the pump, the heater, and the valve assembly, wherein the electronic controller assembly is configured to operate the assembly in a production mode and in a cleaning mode; wherein, in the production mode, the fluid inlet is inserted in or at least connected to the fluid reservoir, such that, during the production mode, fluid to be frothed is supplied to the fluid channel due to the fact that the fluid inlet of the fluid channel is supplied with fluid to be frothed; characterized in that the fluid channel further comprises a fluid restriction, and in that in the cleaning mode, the fluid reservoir and the fluid inlet are disconnected, and in that, during at least part of the cleaning mode, the fluid inlet of the fluid channel is supplied with cleaning fluid.