RODI help!

beausbriggs · Nov 8, 2019

So I have an old RODI unit laying around that hasn’t been used in several years. Decided it was time to set up a salt water mixing station and put the unit back into service, with all fresh filters/media of course. It also seemed like a good time for an upgrade so I added a BRS water saver and an extra DI canister to the unit. Set it up, mounted it, began filling my two 65gal drums and everything seemed great. Output seemed fine, TDS was reading 0, everything good.

Well eventually, after about 75 gallons, the output slowed down to almost nothing. Also, the DI resin at this point was completely spent. Checked the system over and over again and couldn’t find any reasons why. Figured it may be a pressure issue, since my unit is about 100ft from the water source. So I added an inline pump. It helped a bit, but before long I was back to no output. At this point I figured I set up something wrong and started stripping out all the fancy gear (backflush, auto shut off, pump solenoid shutoff, even the water saver upgrade). Still. No change.

So I chalked it up to an old unit and went and bought a brand new BRS 150gal/day unit. Hooked it up with the inline pump and was amazed at the speed I was producing clean water. But then again, DI resin shot at ~50 gallons and the unit kept getting slower and slower. Replaced the resin twice and at about 150 gal produced its barely working.

I’m baffled. What could be the reason? I’m getting ready to fill my new 200 gallon system and I need RO! What should I do?
(Photo is the original unit)

MTBake · Nov 8, 2019

Well water or city water?

Do you have a pressure gauge on the system?

How high is the incoming tds and after membrane tds?

The water flow reducing almost sounds like the sediment filter is getting plugged up. Burning through resin could be fr ok m high co2 in the water supply.

Brien · Nov 8, 2019

Personally, I see the water filter through slower when the tap water is cold. During the summer months it flows much better then during the winter months. You can mix in some warm water but know you're introducing the sediments from your water heater that way. This will result in having to replace your filters more frequently.

beausbriggs · Nov 8, 2019

MTBake said:
Well water or city water?

Do you have a pressure gauge on the system?

How high is the incoming tds and after membrane tds?

The water flow reducing almost sounds like the sediment filter is getting plugged up. Burning through resin could be fr ok m high co2 in the water supply.

City Water... I do have a pressure gauge and it’s reading about 85 psi. I no longer have a TDS before the membrane, but when I did, it wasn’t that high, under 100 for sure. And I can check the sediment filter, but it doesn’t look dirty. I’ve got two, one before the in-line pump, one after.

beausbriggs · Nov 8, 2019

Brien said:
Personally, I see the water filter through slower when the tap water is cold. During the summer months it flows much better then during the winter months. You can mix in some warm water but know you're introducing the sediments from your water heater that way. This will result in having to replace your filters more frequently.

I have the water supply line running through my attic in FL, so even though it’s attached to the cold water supply line, it’s plenty warm!

beausbriggs · Nov 10, 2019

MTBake said:
Well water or city water?

Do you have a pressure gauge on the system?

How high is the incoming tds and after membrane tds?

The water flow reducing almost sounds like the sediment filter is getting plugged up. Burning through resin could be fr ok m high co2 in the water supply.

I just tried bypassing the sediment filter just to see if that was the issue. No change in water output from the system. Any other ideas?

beausbriggs · Nov 16, 2019

is It possible for my RO membranes to clog that quickly?

S.Pepper · Nov 16, 2019

beausbriggs said:
is It possible for my RO membranes to clog that quickly?

I don't know what to say, but I have the BRS 4 stage ro/di system with a water pressure of 50psi and it's working awesome. I checked with my local water dept. and they are treating the water with chlorine, chloride, and phosphate. I also checked the tds before filtering water and it was at 70ppm. I have filtered about 100 gallons of ro/di water and my system is still kicking. I looked at my di resin and it's about 25% used. What is your local water dept. using to treat your water? And what is the tds before filtering your water?