TDS Readings

[toddwess]

The water coming out of my tap is around 219 on my handheld TDS meter.

I've just set up the RO/DI unit last nigh and flushed the membrane for 2 hours, and then ran the system into a bucket for another 2 hours.

I then let it put RO/DI water into my collection drum.

I measured the water this morning and the TDS count is 6.

Is that low enough? Should I throw this water out and wait for TDS to read 1?

Thanks,
Todd

[loganj]

IMO, a TDS of 6 is a little high with a DI chamber. Have you checked the TDS coming out of the RO membrane before it goes into the DI filter? You have a pretty high TDS going in too. How's your water pressure? Low water pressure can cause the RO membrane to operate at a lesser efficiency. You might end up needing to add another DI chamber to get the TDS down to 0-1. Adding a booster pump, if your water pressure is low, would help as well.
If I remember correctly, my readings here were about 170 on the tap, 14 at the RO membrane, and 1 out of the DI filter.

[toddwess]

I haven't checked the water coming out of the RO before it enters the DI yet. Might do that when I get home.

I can't speak to my water pressure. I attached it right to the cold water pipe and we've always had decent water pressure in the house. I wouldn't really classify it as low pressure.

Since it is a new setup, perhaps it is still flushing/cleaning the carbon filter that is after the DI filter (it's a 6 stage).

Thanks,
Todd

[Alf]

I have a 5stage RO/DI out of my tap the TDS is in the 600's. Out of the RO it is a 7 tds out of the DI it is always under 1 when the DI cartrige is new. I change all my pre filters if the RO TDS reaches 15. just me. HTH