Bob999
Reporter
Here is another perspective on SFR that is taken from another website:
I have a paper from Fleck that states as follows:
for Series 9000 Model KO-R-320 32,000 Grains 1.00 Cu. Ft. Mineral:
Peak flow is 19 GPM = 4309 Lit./Hr.
Continuous flow is 14 GPM = 3175
However, resin manufacterrurs define the continuous flow rate through 1 liter of cation resin as 40-42 Lit. of Water/Hr./ Lit. Of resin which brings us to only 5.24 GPM = 1188 Lit./Hr. for Model KO-R-320 32,000 Grains 1.00 Cu. Ft. Mineral.
Resin manufacturers are always more conservative than equipment manufactures. If you want the best possible results in almost all circumstances use the resin manufacturers specifications. Most of the time the equipment manufacturer's specs will work acceptably. I recently saw specs for a 2 cubic ft 13" softener at something like 40 gpm peak flow with a 1 1/2" valve. This seems way out of line to me. You might get the water through it but how soft would it be and how long would the resin last?
You have no mistake. The valve can handle that flow, butas you have correctly noticed the resin manufacturers specify usually about 5gpm per cubic foot. I have always used this rule and called it my rule of 5. A softener can handle slightly higher (peak flow) rates for a short time before hardness leakage will occur.
This is one of the biggest problems in the retail arena since Big Box companies and unscrupulous salespeople alike will not take this into true account when selling to larger families.
I can't tell you how many 3500 to 5000 square foot homes I have seen 3/4 and 1 inch valves on 1 cubic foot tanks installed. Many times reducing from 1 1/4" to 1 1/2" plumbing.
You calculation is more correct for sizing and will serve you and your customers much better for the long run.
There is a definite limit to how fast you can flow water through ion exchange resin. Flowing too fast will result in leakage of ions. You can exceed the resin manufacturers specifications but the quality of the water produced will not be as good. For softening if you flow too fast that will result in higher hardness leakage. Many equipment manufacturers do have high flow rates showing in their specifications for softeners. For residential applications that may not be a problem because most home owners are happy of the hardness of their water is less than 1.5 grains per gallon. That can usually be achieved even when flowing faster than twice the resin specification. However if you follow Jim Wark's recommendations above you will never go wrong.
For commercial/industrial applications it is always best to match the end user's flow rate to the resin manufacturer's flow rate. Most commercial/industrial end user's are sensitive to hardness leakage.
I have a paper from Fleck that states as follows:
for Series 9000 Model KO-R-320 32,000 Grains 1.00 Cu. Ft. Mineral:
Peak flow is 19 GPM = 4309 Lit./Hr.
Continuous flow is 14 GPM = 3175
However, resin manufacterrurs define the continuous flow rate through 1 liter of cation resin as 40-42 Lit. of Water/Hr./ Lit. Of resin which brings us to only 5.24 GPM = 1188 Lit./Hr. for Model KO-R-320 32,000 Grains 1.00 Cu. Ft. Mineral.
Resin manufacturers are always more conservative than equipment manufactures. If you want the best possible results in almost all circumstances use the resin manufacturers specifications. Most of the time the equipment manufacturer's specs will work acceptably. I recently saw specs for a 2 cubic ft 13" softener at something like 40 gpm peak flow with a 1 1/2" valve. This seems way out of line to me. You might get the water through it but how soft would it be and how long would the resin last?
You have no mistake. The valve can handle that flow, butas you have correctly noticed the resin manufacturers specify usually about 5gpm per cubic foot. I have always used this rule and called it my rule of 5. A softener can handle slightly higher (peak flow) rates for a short time before hardness leakage will occur.
This is one of the biggest problems in the retail arena since Big Box companies and unscrupulous salespeople alike will not take this into true account when selling to larger families.
I can't tell you how many 3500 to 5000 square foot homes I have seen 3/4 and 1 inch valves on 1 cubic foot tanks installed. Many times reducing from 1 1/4" to 1 1/2" plumbing.
You calculation is more correct for sizing and will serve you and your customers much better for the long run.
There is a definite limit to how fast you can flow water through ion exchange resin. Flowing too fast will result in leakage of ions. You can exceed the resin manufacturers specifications but the quality of the water produced will not be as good. For softening if you flow too fast that will result in higher hardness leakage. Many equipment manufacturers do have high flow rates showing in their specifications for softeners. For residential applications that may not be a problem because most home owners are happy of the hardness of their water is less than 1.5 grains per gallon. That can usually be achieved even when flowing faster than twice the resin specification. However if you follow Jim Wark's recommendations above you will never go wrong.
For commercial/industrial applications it is always best to match the end user's flow rate to the resin manufacturer's flow rate. Most commercial/industrial end user's are sensitive to hardness leakage.