Automatic electrical controls for household and similar use. Particular requirements for automatic electrical air flow, water flow and water level sensing controls|Air-conditioning systems, Control equipment, Boilers, Air, Cut-out devices, Controllers, Water supply (buildings), Liquid-level measurement, Level control, Control devices, Electric regulators, Liquid controllers, Flow measurement, Safety devices, Flow control, Electric control equipment, Automatic control systems, Water, Electrical safety, Probes, Flow regulators, Electrical household appliances, Space-heating systems, Air control devices, Household equipment