[safeclean uk]

hi there has anyone had any trouble with tds reading after changin membranes in merlin 720 ive just changed both filters and the meter is reading 108-102 i phoned company to ask if there was a problem they said you must run the membranes in and at least run 200 litres through to bring reading down is this right ?

[elite mike]

yes

[safeclean uk]

how much water do you need to run through it then b4 reading starts to drop we been running now an hour and half it still aint come down

[Paul Coleman]

how much water do you need to run through it then b4 reading starts to drop we been running now an hour and half it still aint come down

It should have come down by now.  They can take a few hundred litres to settle in but once they've been in a while it should only take maybe 20+ litres for it to get down to a reasonable level after each start up (assuming you don't have continuous production).  Did youy change the carbon/chlorinew filter too (the top one usually).  Do you have a sediment pre-filter before the main merlin unit?  Is it possible that you seated one of the membranes a bit off centre?

[safeclean uk]

the old membranes had been in 3 yrs wen taking them out i damaged the manifold on the merlin i brought a new one today complete with everything im running water through it like i normally do but reading is still 108 my tap water reading is bout 240 i have no pre filters on just the three supplied with merlin

[The Jester of Wibbly]

I had the same issue.  Turned out the membranes were of a dodgy batch.  When swapped, all went back to normal.