5600 SXT BW - with 12" carbon tank

[Powerless]

Heya,

Local dealer in MX suggested 5600 SXT BW for my 12x52 tank.
I will be able to get power from pump station for small fee.

5600 SXT is speced for up to 10" tank for filters, is oversizing ok ?

Importing other valves from US is neither cheap or easy.

Gracias

 

[Reach4]

I am not a pro. Check everything.

GAC (granulated activated carbon) is a light media. With warmer water, you would want a backwash rate of about 12 GPM/ft2 (yes, that refers to the cross section area). A 12 inch tank would have a cross section of 0.785 square ft. That would come to 9.42 GPM for backwash. The highest DLFC is 7 GPM for that tank, I think. 7 GPM could go 8.91 gpm/ft2 for a 12 inch tank. So I think that controller would max out at 10" x 54" letting you have 1.50 cu. ft. of GAC.

The Fleck 2510 filter controller with mechanical timer would have plenty of backwash ability. http://waterpurification.pentair.com/en-US/product/fleck/2510/ Filters are normally backwashed on a timed basis.

 

[Sponsor]

 

[Powerless]

Reach4 amazing explenation....

I found this chart http://www.purewaterproducts.com/articles/backwash-chart
I guess they say "optimal" is 7gpm

so that's where I would be ? So I think this could work .. I got prices for 2510 out of my price range at this time.

 

[Reach4]

There is a good reason to check! I had seen a source that said 10 to 12 GPM/cuft and I figured you would want the high end of that.

http://www.home-water-purifiers-and-filters.com/calgon-activated-carbon.php is not the source I used initially, but it does name a specific media. Incidentally, you probably do want coconut shell activated carbon. Another term to research.

Found a better source: See the graph on the upper right of http://www.calgoncarbon.com/wp-content/uploads/2015/08/DS-OLC12x4015-EIN-E1.pdf I see people say you normally want 30% to 40% bed expansion during backwash. Note the red line for 72F. That says about 9 gpm/cuft... (splitting the distance between 30% and 40%. The 5600SXT could do that with the 12 inch tank. The tanks are sized with a 50% "freeboard" which leaves room for bed expansion during backwash.

If you had even warmer water normally, imagine a new line that is even lower than the red line. There is probably a formula or graph somewhere for water that is even warmer. But your water may not be warmer on average, so it looks like that 5600SXT could do it based on the Calgon graph. 7 GPM through a 12 inch tank is 8.912 gpm/ft2, so that seems to get you in range.

You know the issues. Let us know what additional stuff you learn.

 

[Powerless]

ahh thank you

I'm planning to load 2 cu ft, with that 5600 SXT.

I will wait for others to chime in.

Gracias

 

[Bannerman]

I guess they say "optimal" is 7gpm

If you read through the linked page above the chart, it indicates "Figures in the chart below are based on average recommendations from media manufacturers." The chart is NOT the optimal rate. Water temperature used in the calculation is also not specified.

The 5600 has limited backwash flow capacity. The manufacturer's capacity specification of 12" for a softener and 10" for a filter is given for a reason. Warmer water as you likely have in Mexico, will only increase the flow rate required to backwash. While it may work for a time, the media will likely fail prematurely if not backwashed thoroughly.