11 Lighting, heating, steam generating and water supply installations, namely, solid, liquid or gas fuel heater, electric heaters, boilers, hot water heaters, non-automatic drains for heating installations, humidifiers, central heating radiators, electric radiators, heating and air conditioning ducts, dampers and plenums, electrical heating filaments, water boilers, water purification apparatus and installations, namely, drinking water filters, water filters, water softeners, water purifiers, water sterilizers, hot water heaters; water distribution installations in the nature of water treatment plants; adjustment and safety attachments for water treatment facilities and equipment; installations for the purification of drain water, apparatus and installations for the treatment and improvement of efficient, sea water desalination installations; water conduit installations comprising pipes, couplings, valves, gauges, meters, pumps, hydrants, and pressurized water tanks