Several European studies have demonstrated that warm-air heating is one of the most efficient heating system for wide premises not always occupied by people, especially when it is possible to check the temperature of the air supplied by the heater and to adjust its volume. In AM premixed gas wall-mounted warm-air heaters both flame and air capacity can be adjusted, granting an unmatched performance of the unit and attaining a highly hygienic combustion. Wall-mounted warm-air heaters are Gas/Air-tight with air/gas premixed burner. Modulating. High performance nearly 94% Low NOx (Nitric Oxide) hygienic combustion CE Certificates according to Gas Appliances Directive 90/396 EEC.