[mgba_78]

As above really, what goes first, tap water to DI then RO or other way round.

Any advantages/disadvantages for either way???

Ta
Andy

[gto]

RO first, then DI.
But only if you need an RO, check you tds/ppm first.

[VSP Home Care]

If this is your static home unit then RO first and polish off with the DI.  But that depends on the RO setup you use and the TDS readings you get from it, if it's good enough then you might not need the DI as well.

[Window Washers]

i would always recommend having a di unless your ro is producing 000 out.

Use 000 tds water and you can never blame the water, it is not expensive to do things correctly.