fluid pumps for fluid transfer and removal in industrial applications, sewage treatment and disposal apparatus and waste water purification units; water treatment and conditioning units comprising demineralizers and water conditioners and valves therefor; fluid filtering units for industrial uses comprising filter elements, filter housings, filter assemblies and component parts thereof for industrial use, filter assembly relief valves, filter cartridges, filter manifolds, filters having microporous layers, membrane filters, dialyzers, coalescers, cyclone and vortex separators oil removal filters, bag filter housings for liquid cartridges as components of disposal and waste water purification units; environmental control systems; namely, air conditioning and heating units, thermoelectric air conditioning units, and heat exchangers; separators for the transfer, reclamation, cleaning and purification of gases, gas dryers; namely, desiccant and refrigerant gas dryers and component parts therefor for industrial uses, cycling control and timing devices for the aforementioned goods, all sold as a unit; and valves as components of gas and fluid dryers and dehydrators