Air filtering installations; Heating installations; Solar heating installations; Ventilation (air-conditioning) installations and apparatus; Air-conditioning apparatus; Desiccating apparatus; Gas scrubbing apparatus; Heating apparatus; Hot air apparatus; Solar heating apparatus; Central heating radiators; Radiators (heating); Solar energy collectors for heating; Solar heating panels; Solar thermal collectors (heating); Water heaters; Ventilation hoods; Fans (air-conditioning); Ventilating fans; Dehumidifiers