Method and apparatus utilizing staged reverse osmosis units for purifying and dispensing water

In a process for purifying and dispensing water using first and second reverse osmosis units with no means for storing water therein, the steps of:

• delivering water under pressure to the feed water inlet of the first reverse osmosis unit, delivering permeate directly from the first reverse osmosis unit to the feed water inlet of the second reverse osmosis unit as the permeate is produced by the first unit, with no storage of permeate between the units, delivering permeate from the second reverse osmosis unit to a storage tank, dispensing water from the tank, interrupting operation of the reverse osmosis units in the event that the water in the tank rises to a first predetermined level, resuming operation of the reverse osmosis units in the event that the water in the tank drops to a second predetermined level, collecting water spillage from the reverse osmosis units and tank in a sump pan positioned beneath the same, and pumping the water from the sump pan to a drain in the event that the water in the pan reaches a predetermined level.

In a water purifying and dispensing machine:

• a cabinet, water inlet means for connection to a source of feed water, first and second reverse osmosis units, a first pump for delivering feed water from the inlet means to the feed water inlet of the first reverse osmosis unit, a second pump for delivering permeate from the first reverse osmosis unit to the feed water inlet of the second reverse osmosis unit, a reservoir within the cabinet for holding purified water from the second reverse osmosis unit, a dispensing station accessible externally of the cabinet, coin operated means for delivering water from the reservoir to the dispensing station, a sump pan toward the bottom of the cabinet positioned for catching water from other portions of the machine, a pump for delivering water from the sump pan to an external drain, and level responsive means for actuating the pump in the event that the water in the sump pan reaches a predetermined level.