Latest Tweets

Ciphe Registered Plumber

UKWTA Company Essex

Free Delivery

Simplex or Duplex?


The two most common types of water softeners used in commercial water softening plants are simplex water softeners and duplex water softeners.

Simplex Water Softener

water-softener-open diagramSimplex water softeners are best suited to consistent demand applications of moderate total water consumption. The regeneration process is controlled by the multiport valve head assembly located at the top of a single vessel which is connected to a seperate brine tank (see diagram above). Timer clock controlled or meter controlled water softeners can either be set for an immediate or delayed regeneration, preferably when water demand is low. During the regeneration process the single vessel control valve will bypass hard water to service unless a bypass lockout facility is specified. The correct sizing of simplex softeners is crucial as the system will need to give at least one days softened water output before regeneration.

Duplex Water Softener

Duplex water softeners give a 24 hour supply of softened water. Duplex systems use two resin vessels, one in service, the second on standby. The water flow to service is metered and when the service column is Duplex Flow Diagramexhausted, the control valve automatically switches, allowing the second unit to go online. The exhausted resin in the first column is fully regenerated and remains on standby until the second column is exhausted, then the control valve switches back to the first column again. A duplex water softener can be sized to allow up to 4 regenerations in any one 24 hour period. Parallel systems with both vessels on line at the same time are also available. A duplex water softening system is better suited for applications where a 24 hour constant supply of softened water is required or where times of water flow are varied. Using two smaller resin vessels as opposed to a large single simplex system can reduce the height of your softening system dramatically.