Abstract: A portable surface cleaning apparatus has a base for movement along a surface to be cleaned and an upright handle pivotally attached to a rearward portion of the base. A fluid dispensing nozzle for applying fluid to the surface and a suction nozzle for picking up fluid and debris from the surface are associated with the base. Supply tanks are removably mounted to the handle or base while a recovery tank is removably mounted to the handle or base. An outlet in each supply tank includes a valve to close the outlet when the supply tank is removed from the base. A float valve assembly in the recovery tank includes a first end for covering an air outlet port from the recovery tank and a second end, which is buoyant and elevated by the rising recovered fluid in the tank, for raising the first end to cover the air outlet port.