Testing and reconnecting Kinetico 2020C Water Softener After 3+ Years Unused -DIY??

Section62

WIAWSNB said:

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The HE/HF versions seem to be as you say, the latter being able to handle a higher flow rate. Hard to think of how it can affect performance and operation, tho', as the two systems types - vented and unvented - can outdo eachother in individual circumstances. 
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As above, if the HE model had some kind of flow restrictor it would mean the water could spend more time in the ion exchanger and therefore be softened by a greater degree.  The reduced flow wouldn't matter if there is a storage tank, but could be a problem if everything is mains-connected.

Another possibility could be that the HE model has a smaller granule-size in the ion exchanger (=more surface area=greater efficiency) but then needs a finer filter on the outlet to stop the granules leaking out.  A finer filter would then have the effect of restricting the output flow to a greater degree than a coarser filter which could be used Ok with larger granules/beads (but, =less surface area=lower efficiency).

Would be interesting if sujsuj can get some feedback from Kinetico on the difference.