[rvs]

i recently bought a second hand pole system and all seemed fine i was getting 18 tds into the tank  after a few fills i washed thru with salt now my tds is 107 does this mean my ro has had it

[JM123]

what type of system is it?  Is it a 4040RO??  How old is the ro itself and have the prefilters been changed recently??

[rvs]

IVE JUST CHANGED THE PRE FILTERS AND ITS A 40 INCH RO  BUT THE WATER HERE IS ABOUT 360 FROM THE TAP

[rvs]

OVER 2 HOURS RUNNING IT WITH OUT USING THE I E ALL 80 PER CENT AND 20 PER CENT TO WASTE THE READING IS NOW 95  IS THIS NORMAL

[freshwater]

rvs

What have you washed through with salt? not the membrane I hope.

If you have a softener before the RO thats what needs the salt.

Do you have de-min resin after the membrane, if you have, check the TDS before the de-min and compare with TDS after the de-min, if they are the same or similar you need to chage the de-min resin.

If you are getting 107 out of the membrane on an input of 360 either your pressure is to low or the membane is shot.

4040 are designed to work at 100psi but they will work at lower pressures.

steve@freshwatersystems.co.uk

[edd]

the waste should be 40% 50% after a salt back wash on mine the tds is 007 ish after the di resin its 000 my tap water is 340 tds hope this helps Edd also flush the ro at once a week intervals

[JM123]

nnnnnooooooooo!!!!!!!!!!

please tell me you didn't use the salt to backwash the membrane? the membrane is self flushing although turning the flush valve completely open once a week doesn't do any harm.  Hows the membrane performing now? 

[edd]

i did not mean the membrane i have got salt back wash resin above the ro mine is the thermo pure system

[freshwater]

It is the softening resin and not the de-min resin. If it is the softening resin that’s OK. With such a high reading its either you membrane, your water pressure, or your de-min resin.

Test the TDS at the outlet of the membrane and compare it with the TDS after the de-min resin, if they are the same the  de-min needs changing. If the reading is high then this also means either the membrane is shot or you have low water pressure. If you don’t have one then fit a pressure gauge to the inlet of your system.

Once you have got a pressure reading if it’s below 60psi the chances are on a 4040 with your initial high TDS you will be relying on the de-min resin. If this is case get rid of the expensive throw away de-min filter which only holds 6-7 litres of resin (at over £60 a time) on the Thermopure and replace it with a vessel, we sell an 8 x 17 vessel inc all internals for £80 you can then add 10 litres of resin. Much more cost effective.

If you water pressure is 60psi plus then is probably time for a new membrane.

steve@freshwatersystems.co.uk