A cleaning appliance

The present invention relates to a cleaning appliance 2 and particularly to a cleaning appliance comprising a main body 6 and a cleaner head 4, the cleaning appliance comprising an improved system for controlling and communicating with a cleaner head. In particular, the present invention provides a cleaning appliance wherein the main body is configured to supply power to the cleaner head via a plurality of conductors, and wherein: the main body comprises a first controller configured to modulate the supply of power to the cleaner head, and the cleaner head comprises a second controller configured to detect a modulation in the supply of power and, responsive to the modulation, control a component of the cleaner head. The first controller may be configured to modulate the power supply by: pausing the supply of power, adjusting the pulse-width modulation (PWM) frequency of the supply of power and/ or adjusting a PWM pulse width of the supply of power.