Heat accumulators; steam accumulators; air conditioning apparatus; air cooling apparatus; air dryers; air purifying apparatus; air purifying machines; air reheaters; pipes for heating boilers, namely, boiler pipe tubes for heating installations; distillation apparatus not for scientific purposes, namely, coils being parts of distilling installations; coils being parts of heating installations; coils being parts of cooling installations; gas condensers, other than parts of machines; cooling installations for liquids, namely, closed circuit glycol/water radiators not for use in vehicles, and evaporative liquid coolers; cooling installations for water; drying apparatus and installations, namely, industrial pressure swing and temperature swing absorption dryers, refrigerative dryers; fuel economizers, namely, devices for warming feed water in heating boilers, gas to gas economizers in refrigerative dryers; fans for HVAC units, namely, air-conditioning fans; fans being parts of air conditioning installations; filters being parts of industrial installations, namely, water filters, air filters for industrial installations, and filters and filtering devices for air and gas conditioning, namely, gas dust filters and gas coalescing filters; flare stacks for use in the oil industry; flares; boilers for heating installations, namely, gas boilers; biogas generator installations, namely, anaerobic digestion to power biogas engines, landfill gas to power biogas engines; gas scrubbers for use as parts of gas installations; gas scrubbing apparatus; heat exchangers not being parts of machines; heat exchangers not being parts of machines, namely, shell heat exchangers, tube heat exchangers, and air cooled heat exchangers; heat exchangers not being parts of machines, namely, stainless steel and titanium plate heat exchangers; heat generators; immersion heaters; heating boilers; hot water heating installations; heating plates, namely, hot plates; oil scrubbing apparatus in the nature of oil purifying installations; refrigerating apparatus and machines, namely, industrial water/glycol chillers; heating boilers in the nature of steam boilers other than parts of machines; steam generating installations; water heaters and apparatus, namely, water heaters, feed water heaters for industrial purposes, hot water tanks, clean-in-place (CIP) electric and steam fired heaters, and calorifiers in the nature of heating units for industrial purposes; scrubbing towers, namely, industrial water scrubbers for removing water soluble gases from raw biogas, particulate matter from the air during industrial processing, namely, impingement scrubbers, venture scrubbers, dynamic scrubbers; stripping towers, namely, for the stripping of gases from water; gas purification systems comprised of gas purification machines; biogas purification apparatus in the nature of gas purification machines; landfill gas purification apparatus in the nature of gas purification machines; pressure vessels for controlling the flow of water and gas through water purification machines and gas purification machines; Cooling appliances, namely, fin-fan radiators not for use in vehicles, and industrial refrigeration chillers; cooling installations in the nature of cooling units for industrial purposes; air conditioning installations; gas condensers, other than parts of machines; gas purifiers in the nature of gas purification machines; heat accumulators; heat regenerators in the nature of regenerative heat exchangers; mechanical fuel economizers for the recovery of heat contained in flue gases; coils as parts of distilling, heating or cooling installations; heat pumps; heating installations