Abstract: Liquid dispensing apparatus includes a tank for storing liquid to be dispensed, a fill line communicating with an interior of the tank and adapted to be coupled to a source of the liquid, a heating element for heating the liquid, a heating control device for controlling the heating element to heat the liquid to a predetermined temperature, a dispensing device for dispensing liquid from the tank under pressure and a dispensing control device for selectively controlling the dispensing of the liquid by the dispensing device. The fill line is adapted to be connected to existing plumbing, such as a toilet water supply line behind a wall adjacent the toilet. The tank is adapted to be housed in a recessed wall cabinet adjacent the toilet so that the entire apparatus is hidden from view when not in use. The tank includes a sump portion defining a lowermost portion of the tank, to facilitate complete evacuation of liquid from the tank.