To provide a washing-only car equipped with an engine, a water boiler, etc. for washing outer walls of a building etc., which car prevents the outer face from being heated up by heat generated inside for safety against a skin burn, is equipped with engine noise measures, and is structured to reduce air vibration inside and to prevent failure of parts.

This washing-only car is equipped with equipment required for jetting out high pressure hot water inside the equipment room. Heat insulation, sound insulation, and sound absorption are applied on inner faces of the equipment room of the car. The equipment room can be used as a washing-only gondola by equipping a gondola for building outer wall washing equipped with equipment inside for jetting out high pressure hot water.