The diagram shows a simple method for conserving water using the reject RO water as opposed to discharging to drain. In most cases we use 300 gallon storage tanks, one for the spot free water and the other for reclaim/reject water for wash / wax and initial rinse prior to spot free if fresh water is not used. The float switch will allow reclaim water to maintain a minimum tank level through a 24 vac solenoid in the event that the reject can not keep up to demand. This tank is also equipped with an overflow to drain. The float switches in the RO tank are for high level and low level control. This particular drawing is for a reclaim system with fresh water back up if required. We still are using fresh soft water only for chemical mixing and primary rinse in some cases. 

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