RO/DI question

[epleeds]

I accidentally left my water running without the booster pump on and realized after about a week.  i have low water pressure, but it did fill my RO containter to the top.  since the booster pump was not running, it is okay to use since it wasn't forced through the system with the higher pressure?

 

or should i just dump it out and start again?

 

 

[YHSublime]

I'd use it, but I have no science or logic to why.

[Crob5965]

I would still use it, saying that I got a bunch of sawdust in mine last month and I still used it, do you have a TDS meter?

[DuffyGeos]

+1 Yea, I was going to say test it with a TDS meter. I think the pressure rating is to prevent too much waste water. It had to go through your entire RO/DI system to end up in your container so it was filtered. - right?

[epleeds]

thats what i thought, but i always like a second opinion.  thanks

[davelin315]

Yes, the water is fine. The average membrane does the best job and wastes the least water at around 75 degrees and around 80 PSI (some are different, but the typical ones are in that vicinity). A booster pump si ply boosts the pressure in low pressure systems to the point where more water is forced through the membrane elvers us being rejected. It is kind of like trying to blow a ballon up passively by blowing air at it versus sticking it in your mouth and blowing, more pressure equals more filling.

[DaveS]

Water is fine, di resin may have gotten exhausted tho.

[davelin315]

Water is fine, di resin may have gotten exhausted tho.

I think it would be the opposite end of the filters. If the DI is the last stage, it filtered only what went through the membrane. The prefilter, GAC, and carbon block, however, processed an awful lot of water if it was running straight up for the week.

 

In ideal situations, I think most of the RO units process at about a 4:1 ratio, or reject around 80% of the water that flows through it. In a low pressure situation, I would assume the wast goes up substantially and if you theoretically produce 75 gallons of water per day then your waste water would be around 400 gallons per day. Over e course of a week, that is close to 3,000 gallons of water that flowed through your prefilter stages...

[DaveS]

I think it would be the opposite end of the filters. If the DI is the last stage, it filtered only what went through the membrane. The prefilter, GAC, and carbon block, however, processed an awful lot of water if it was running straight up for the week.

 

In ideal situations, I think most of the RO units process at about a 4:1 ratio, or reject around 80% of the water that flows through it. In a low pressure situation, I would assume the wast goes up substantially and if you theoretically produce 75 gallons of water per day then your waste water would be around 400 gallons per day. Over e course of a week, that is close to 3,000 gallons of water that flowed through your prefilter stages...

Suboptimal water pressure means lower rejection rate for membrane. That means the di was likely the first thing burned through. The fact that it was left open ask week means possibility that the other filters are also shot. But my instinct is that the di went first.

[Origami]

Eric, the water is probably fine. If your DI resin exhausted, though, then the product may have high TDS. The way to check is with a handheld TDS meter.

 

The other filters have a lot more capacity than the DI resin, especially if you're on city water. Running at low pressure would likely exhaust the resin first before the other filters, but all filters would have suffered a little extra.