Machines and equipment for heating gas, liquid and solid products; water heaters; heating apparatus for solid, liquid or gaseous fuels; heat pumps; heating boilers; steam boilers, other than parts of machines; heat accumulators; heat regenerators; chimney flues; gas condensers, other than parts of machines; parts of gas installations named scrubbers; parts of gas installations named gas scrubbers; distillation apparatus; distillation columns; stills; evaporators; water filtering apparatus; furnace bars; coolers for furnaces; cooling vats for furnaces; installations for gas generators; incinerators; pasteurisers; gas burners; recuperators; refrigerating appliances and installations; cooling appliances and installations; cooling installations for water; cooling installations for liquids; drying apparatus; coils, named parts of distilling, heating or cooling installations pressure water tanks; expansion tanks for central heating installations; boiler pipes for heating installations; steam accumulators; steam generating installations; boiler absorber-evaporator machine