Water Running slow thru RO/DI

tank41 · 08/09/2011, 02:50 PM

Hey guys. I am just curious. I have noticed quite a decrease in water exiting the RO/DI system. It used to be a light stream. Now it is just dripping slowly. I changed sediment filter and the carbon filters and still just dripping slowly. The membrane is probably 2.5 years old. Could this be the culprit. If so can they be rinsed some how or cleaned or is it just time to shell out some bucks for a new one.
Any advice is appreciated.
Thanks

Hujoweforum · 08/09/2011, 03:05 PM

I always change the membrane every two years. Acid baths do work but at a diminishing return on TDS.

snorvich · 08/09/2011, 03:24 PM

Water pressure may be an issue. I use a booster pump.

snorvich · 08/09/2011, 03:24 PM

Also, what does your TDS meter read?

tank41 · 08/09/2011, 03:33 PM

Hey thanks for the tips. TDS is zero coming out of the DI

Hujoweforum · 08/09/2011, 03:45 PM

Check the TDS on the membrane and then on the source water and you can calculate the rejection rate. Filmteck membranes are the highest rejection at 98.5% most are 98%. I bet you may be lower.

Hujoweforum · 08/09/2011, 03:48 PM

If you have a high rejection right 96-98% prior post is correct its your psi.

allsps40 · 08/09/2011, 03:48 PM

I know when my sediment and carbon filters need to be changed my flow slows way down and the pressure at the membrane drops.

Hujoweforum · 08/09/2011, 04:06 PM

with the cartridges already done my guess is the membrane at 2 1/2 years. The source water temperature changes product water speed but that would not be the case. In the midwest you see huge changes in product water based on ground water temperature. Winter is slow summer is great. I change membranes going into the cold period for that reason.

tank41 · 08/09/2011, 04:29 PM

Guys one more thing I noticed is that the waste water is running all the time at a good flow. More then the water exiting the DI. Does that tell me anything? One more thing. The wast water is running all the time even when my float switch turns off my ro system. The ATO is a level loc and water is fed directly to my sump from the RO/DI but I don't remember the waste water running when the RO is shut off via float switch. Is it suppose to???
Thanks again.

Hujoweforum · 08/09/2011, 05:13 PM

The float is the product water, the waste water is the water going down the drain. Without a solenoid the waste water won't shut off. Which may be your setup.It looks like a white(usually) box that has the in from your units lines and out to the drain and float switch. four total.

08/09/2011, 02:50 PM	#1
tank41 Registered Member Join Date: Apr 2008 Location: Sioux City, Ia. Posts: 332	Water Running slow thru RO/DI Hey guys. I am just curious. I have noticed quite a decrease in water exiting the RO/DI system. It used to be a light stream. Now it is just dripping slowly. I changed sediment filter and the carbon filters and still just dripping slowly. The membrane is probably 2.5 years old. Could this be the culprit. If so can they be rinsed some how or cleaned or is it just time to shell out some bucks for a new one. Any advice is appreciated. Thanks

08/09/2011, 03:24 PM	#3
snorvich Team RC member Join Date: Aug 2005 Location: Outlander Posts: 40,953 Blog Entries: 46	Water pressure may be an issue. I use a booster pump. __________________ Warmest regards, ~Steve~

08/09/2011, 03:24 PM	#4
snorvich Team RC member Join Date: Aug 2005 Location: Outlander Posts: 40,953 Blog Entries: 46	Also, what does your TDS meter read? __________________ Warmest regards, ~Steve~

08/09/2011, 03:48 PM	#8
allsps40 Registered Member Join Date: Aug 2010 Location: Arizona Posts: 4,627	I know when my sediment and carbon filters need to be changed my flow slows way down and the pressure at the membrane drops. __________________ __________ Current Tank Info: Past reef tanks: 20H softy, 29G mixed reef, 55G mixed reef, 40B sps dominant mixed reef and 75G sps dominant mixed reef. No tank currently

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08/09/2011, 03:05 PM	#2
Hujoweforum Registered Member Join Date: Aug 2011 Posts: 93	I always change the membrane every two years. Acid baths do work but at a diminishing return on TDS.

08/09/2011, 03:33 PM	#5
tank41 Registered Member Join Date: Apr 2008 Location: Sioux City, Ia. Posts: 332	Hey thanks for the tips. TDS is zero coming out of the DI

08/09/2011, 03:45 PM	#6
Hujoweforum Registered Member Join Date: Aug 2011 Posts: 93	Check the TDS on the membrane and then on the source water and you can calculate the rejection rate. Filmteck membranes are the highest rejection at 98.5% most are 98%. I bet you may be lower.

08/09/2011, 04:06 PM	#9
Hujoweforum Registered Member Join Date: Aug 2011 Posts: 93	with the cartridges already done my guess is the membrane at 2 1/2 years. The source water temperature changes product water speed but that would not be the case. In the midwest you see huge changes in product water based on ground water temperature. Winter is slow summer is great. I change membranes going into the cold period for that reason.

08/09/2011, 04:29 PM	#10
tank41 Registered Member Join Date: Apr 2008 Location: Sioux City, Ia. Posts: 332	Guys one more thing I noticed is that the waste water is running all the time at a good flow. More then the water exiting the DI. Does that tell me anything? One more thing. The wast water is running all the time even when my float switch turns off my ro system. The ATO is a level loc and water is fed directly to my sump from the RO/DI but I don't remember the waste water running when the RO is shut off via float switch. Is it suppose to??? Thanks again.

08/09/2011, 05:13 PM	#11
Hujoweforum Registered Member Join Date: Aug 2011 Posts: 93	The float is the product water, the waste water is the water going down the drain. Without a solenoid the waste water won't shut off. Which may be your setup.It looks like a white(usually) box that has the in from your units lines and out to the drain and float switch. four total.