HVAC units; HVAC equipment; Heating, ventilation and air conditioning (HVAC) systems comprising HVAC units, fans for HVAC units, control panels, and air filters for HVAC units for commercial use and replacement parts and fittings therefor; cabin-filter pressurizer in the nature of an air purifying apparatus; air filters for HVAC units; fans for HVAC units; custom HVAC units and accessories thereof; HVAC units for commercial purposes; Cooling units for commercial purposes; Heating units for commercial purposes; Air conditioning units for commercial purposes; Climate-control units for commercial purposes; Ventilation units for commercial purposes; HVAC systems for commercial purposes; Cooling systems for commercial purposes; Heating systems for commercial purposes; Air conditioning systems for commercial purposes; Climate-control systems for commercial purposes; Ventilation systems for commercial purposes; Commercial climate-control system for ventilation, heating and cooling; Industrial ventilation systems; Industrial ventilation systems to control air pollution and clean the air in commercial, education, retail, and industrial settings; Design and development of HVAC units; Design and development of cooling units; Design and development of heating units; Design and development of air conditioning units; Design and development of climate-control units; Design and development of ventilation units; Design and development of HVAC systems; Design and development of cooling systems; Design and development of heating systems; Design and development of air conditioning systems; Design and development of climate-control systems; Design and development of ventilation systems