11 Ice machines; refrigeration systems comprised of compressors, motors, condensers, evaporators, heat exchangers, control panels, thermostatic expansion valves, dryers, sight glasses, temperature gauges, and pressure controls; ventilation and air conditioning equipment, namely, ducts, fans, blowers, motors, and control units; heating units, namely gas burning heating units, electrical convector heating units, radiant heating units, forced air central heating units, heating and cooling coils; and parts, supplies and materials therefor