Flues and installations for conveying exhaust gases in the nature of chimney flues, flues for heating boilers; oil and gas burners for industrial use; oil and gas burners for commercial use; oil and gas burners for domestic use; boilers for heating installations; air heaters; cooking apparatus in the nature of cooking stoves; heating apparatus for furnaces; refrigerating apparatus in the nature of electric refrigerators; fireplaces, domestic; air filters for industrial and household use; industrial treatment installations in the nature of water treatment apparatus, namely, clarification and thickening machines for use in treatment of liquids in the nature of water, waste water and industrial water; industrial installations for the filtration of liquids in the nature of water treatment equipment, namely, water filtration units; installations for the collection of gases in the nature of gas recycling systems comprised primarily of pressure swing adsorption equipment for the recovery, purification and return of gases in industrial applications, mechanical or thermal recompression systems for evaporators and crystallizers, and gas product recovery systems; installations for the collection of liquids in the nature of drain pans specially adapted for water heaters to protect from condensation, leaks, and overflow; bioreactors for clarifying industrial waste water being bioreactors for use in the treatment of waste water; apparatus for draining food waste in the nature of apparatus for dehydrating food waste; drying installations in the nature of drying apparatus for use in heating, ventilation systems, air conditioning systems, and refrigeration systems; refrigerating equipment, namely, rapid food chilling units; freezing equipment, namely, freeze drying equipment, namely, lyophilizers; regulating and safety accessories for water and gas installations; heating equipment in the nature of heating installations; ventilating and air conditioning equipment in the nature of air-conditioning, air cooling and ventilation apparatus and instruments; air purification equipment in the nature of air purifying units for commercial use; air purification equipment in the nature of air purifying units for domestic use; air purification equipment in the nature of air purifying units for industrial use
