[QUOTE=Gary Slusser;334148]IMO, using a chart used for boilers etc. to size or set up a residential softener is not the right way to go because normally the equipment is not the same nor is the water quality from a residential softener acceptable for most commercial boilers.
If we were to use the chart, I see a 6-8% increase in efficiency from 5 to 7 or 8 days and IMO again, 6-8% over the 10-20 years of the normal life of a residential softener seems like a fair amount of salt saved. Or, we could say a substantial increase in salt efficiency.
And I do not believe the "efficiencies" are talking about water efficiency, just salt used. Water efficiency would be greatly increased with 7-8 day regeneration.
Residential softeners should be sized and programmed for a regeneration on average every 7-9 days, using 60 gals/person/day.[/QUOT
We use the exact same equipment for commercial boilers as we do residential. For small steam boilers requiring <1-3ppm hardness as CACO3, any Fleck or Clack can be used to meet this water quality requirment. Just use your resin manufacturers hardness bleed charts. A hardness bleed of <2 ppm can be achieved by regenerating a resin bed with 12-15 pounds of salt per cu. ft. This is not an acceptable efficiency for most operators, so a pre-softener, usually a twin alternating design is installed ahead of the polishing softener. The pre softener is typically set to regenerate with 4 pounds of salt per cu. ft. BTW, I am a licensed steam boiler operator.
My charts are a standard efficiency chart. We use it to show the diminishing return past a certain point. In steam boiler and cooling towers we use this for water cycles. If I increase my water cycles past 6, the return on efficiency drops neglibly. Same goes for salt efficiency past 85-90% efficiency. Why not go to 14 days between regenerations from 7 days, that is an increase of 7%, over 20 years...
The point of the chart is not to create an efficiency debate, I will win that one every time. I was a system efficiency consultant for SCE and SCG, I know how to maximize systems efficiencies in softeners, electrical systems, Cooloing towers, steam boilers, lighting systems, motors, etc.
I will try to find the article I wrote 10 years ago on this exact subject and post it, otherwise look up Pentairs water/salt efficiency article. A cubic foot of resin uses a nearly set amount of water to regenerate. I agree that systems should be sized to regenerate every 7-9 days, but as long as they meet the 5 day minimum, the efficiency differences are no where nearly as dramatic as some people would beleive.
Tom has it right, a system set to regenerate with a proper amount of salt and I will add, systems should have their backwash and fast rinse times minimized to meet the supply water quality, then as an industry we will have met a much better standard than we have in the past. Considering the largest system people buy from Home depot will usually regenerate every day or two...
Now for micro managing salt usage, I used to sell millions of pounds of salt to commercial and industrial facilities, and we pushed for innefficent systems to increase our salt sales. Not a good way to do it, and we are now heavily regulated because of our short term thinking of the past. Also in the past, the technology was just coming in to allow for easy efficiency gains. I rarely sell single tank systems anymore for commercail applications, the majority of our larger system sales are almost always system 14 triplex designs. We do not need to micro manage salt, just properly sell systems that are sized properly, and set the salt to less than 8 pounds of salt per cubic foot and the customers will nbe happy, and we will keep ourselves from being more regulated. See the capacity vs salt chart aboe to see why 8 pounds should be the max. The efficiency curve drops quickly past 8 pounds. California allows for no more than 6 pounds for residential use. I do not like 6 pounds personally beacuase of the hardness leakage gets into the area where some people do not "feel" the full benefits of soft water.
Lets not start a debate, just look at the charts, nod , and dont start stirring.