Retail services related to apparatus for heating, drying and ventilation, fans (parts of air-conditioning installations), fans (air-conditioning), electric fans for personal use, parts and components for fans and ventilating apparatus including sound dampers, intake screens, back draft dampers, fire valves and shutter valves, inlet and outlet supply/exhaust connections, connections, air seals, ventilation ducts and ventilation units, ventilation hoods, supply-air units, speed controls for fans, duct heaters, supply-air and exhaust-air devices, suction hoods for kitchens, thermostatic valves (parts of heating installations), level-controlling valves in tanks