Hi Miles,
I understand your flushing circuit description, that seems like a great idea especially if you have to winter in the cold every year.

As I understand it from this thread, neither the glycerin solution nor the propylene glycol will cross the membrane, so it seems to be still important to drain any desalinated water from the output side, including the flow-meter tube.

Many thanks again to all
Dean
SY Stella
A54-154



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