Sorry @Greybeard, I know this is an old post, but I’m hoping you can help me a bit to understand where to put a permeate pump in a brs drinking water/reef RODI system. You say that the permeate pump replaces the auto shut off valve. Does it get plumbed into the same spot that the auto shut off valve in a typical BRS system is found? And do you place the check valve before or after the final carbon block on your drinking water line?
@KStatefan did a good job on showing how it all works...
AirWaterIce, my RO/DI vendor, has an installation document here:
And, swiped shamelessly from that document, their install diagram:
Hope this helps!