HVAC systems in the nature of HVAC units; parts of HVAC systems, namely, component parts for HVAC units; heat pumps; Parts for heat pumps; heat exchangers not being parts of machines; filter driers, namely, commercial filter driers for refrigeration and air conditioning installations; expansion valves, in the nature of thermostatic valves as parts of heating installations; None of the aforementioned products intended to be used for modular building units or building constructions in a modular...