Hydronic boilers and heaters use hot water or steam to provide the primary source of heat in cold weather. They connect to the building's hot water supply and use gas or oil as fuel. Hydronic duct heating and cooling coils use hot or chilled water to produce supplementary warm or cool air. Whole-house water and steam boilers provide heating throughout a house. Hydronic baseboard and floor heaters install close to the floor to provide heat from the ground up in offices, hallways, and other small spaces. Hydronic wall and ceiling heaters mount on walls and ceilings to provide warmth without taking up floorspace in areas like warehouses, manufacturing facilities, and garages.