[dave0123]

changed my pre filters the other day using this one from gardiners

http://www.gardinerpolesystems.co.uk/acatalog/carbon-block-filter-10-inch.html

for carbon block and the usual sediment one.


TDS has suddenly risen from my usual 20 to 34 .. anyone got any ideas why?  i did notice the carbon block filter was wasn't a yellow ish colour this time when new and was completely white. anyone else noticed this? have they changed them slightly?

[Smudger]

New filters should be lovely and white how long we're they in before change over and the TDS used to be ?

If the TDS was 30+ from the start it may not have bedded in yet,  if its crept up then maybe one of the filters hasn't sealed quite right although these shouldn't effect the membrane

What membrane you got how old and what water pressure ?

Darran

[dave0123]

i don't mean there dirty, i mean there a yellow type from when made its a yellow plastic that there made out of. these new ones are white for some reason slightly different make maybe that gardiners have stocked instead?

the TDS used to stick around 20-25 i do have low pressure of about 14 psi but its been in these conditions for while now well years.. i cant remember how old the membrane is probably 3/4 years old but it doesn't get used as often as most lads on here. certainly not every day.

ive checked the filters to see if they were not seated properly.

[dave0123]

it hasnt crept up slightly either, last time it was used it was producing 20 tds.. now suddnley 34

[Alex Gardiner]

changed my pre filters the other day using this one from gardiners

http://www.gardinerpolesystems.co.uk/acatalog/carbon-block-filter-10-inch.html

for carbon block and the usual sediment one.


TDS has suddenly risen from my usual 20 to 34 .. anyone got any ideas why?  i did notice the carbon block filter was wasn't a yellow ish colour this time when new and was completely white. anyone else noticed this? have they changed them slightly?

It is always best practice to flush any new carbon pre-filters for about 10-15 minutes before attaching to the RO membrane circuit (these instructions are on our website product description). This is to flush out any loose carbon fines within the filter. If this has not been done then it may simply be the presence of these loose carbon fines that are making the TDS read higher. The solution if this is the case should be to disconnect the pre-filters from the RO membrane and flush for about 10 minutes.

However if this higher TDS reading is after the RO then it may be that these carbon fines have damaged the RO membrane itself. To try and rectify in this case then flush the RO membrane for 1/2 hour (having already flushed the pre-filter) and then re-test.

[dave0123]

Hi Alex,

I have flushed them for about 1 hour when i got them the last week. must admit i didn't disconnect the inlet to the membrane when doing this.

I haven't made any pure water until now because i already had some in the ibc for weeks work. ive had it flushing for a while now will test it again later on.


just to clarify, i have had the membrane for just hitting 5 years  don't use it a lot probably only once per week to produce pure but keep it flushed and wet.

[Alex Gardiner]

This will mean that all the loose carbon fines in the new filter (which all carbon block filters have) will have gone into the RO membrane.  If you are fortunate this will not have permanently damaged it.  If this is the case then flushing the membrane for an hour may rectify the TDS readings.  If this does not rectify it, then the carbon fines will have damaged the RO membrane permanently 

[dave0123]

thanks Alex.

weirdly enough ive never actually disconnected the pre filters from the membrane when changing the pre filters before... maybe just been lucky in the past.


i will leave it flushing for a few hours i think and try again.