Fleck 5600SXT Carbon Filter Issues

[Ryan Smith]

I use chlorine to oxidize iron in my water. Following the settling tank I have a backwashing carbon filter. It's a Fleck 5600SXT on a 10x54 with 1.5cuft of GAC. It came set up with a 6GPM DLFC. In the first couple cycles I did notice some media out the drain line, but I just figured that was fines from the new media. The water quality was so improved from our old Iron stained water I just didn't think too much about it, but now I'm wondering if I should have paid more attention to that.

The current issue is that I have no flow during Rapid Rinse (if I listen carefully with my ear on the valve it does sound like there might be a tiny bit of flow, but just a trickle). I just happened to be there at the right time and noticed it. Water quality has been good and the system has been in place for about 4 years. Backwash flow is normal. Today I disassembled the valve the only issue I could find was that one of the piston seals was torn up and in pretty rough shape. That needs to be fixed, but I don't think that explains why there is no flow during Rapid Rinse.

Is 6GPM maybe too much for the backwash and media is getting up in the valve, causing the damaged seal? Any tips on what to check if Backwash works fine but there's no flow in Rapid Rinse. I've got new GAC and looking to do whatever is needed to the valve to make sure I'm set for the next few years.

 

[Reach4]

You should have let the new GAC soak in water before backwashing. You also should have started with a slowed-down backwash by using the bypass valve at a partially bypassed setting.

Did you change the programming by chance? What is the setting for VT?

 

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[Ryan Smith]

Thanks for the reply! I didn't pre-soak the GAC originally but will be sure to do so with the new stuff. Makes sense to start with the slow backwash too. I'll definitely do that.

No changes to the programming. VT is set to Fltr.

 

[Bannerman]

Carbon contains fine particles, 'Fines', that need to be flushed from the media before use. The soaking process permits the carbon media to become saturated with water. Unsaturated carbon contains air within the carbon's pores which cause the media to be highly buoyant and easily backwashed upward within the media tank where it will be forced against the upper screen which will increase the potential for media loss and breakage of the upper screen.

The recommended soak time is 48 hours if possible followed by at least a 20-minute rinse initially.

The article linked below, describes the recommended startup procedure for softeners and carbon filters. https://view.publitas.com/impact-water-products/2018-catalog-final/page/36-37

When obtaining new carbon media, remember to also obtain an appropriate quantity of bedding gravel. For a 10" diameter tank, 15 lbs of 1/8 X 1/16 (#6) gravel is recommended.

 

[Ryan Smith]

Thanks guys! Any thoughts on the no flow during rapid rinse issue? I just can't understand that one. I tried digesting the diagrams in the 5600SXT Service Manual but it's hard to see what could cause this. The diagrams are really low resolution though and it's tough to see exactly what's going on.

 

[Reach4]

Do both the old and new pistons have the green cap? (60102-71)

 

[Ryan Smith]

I haven't changed any parts yet. The current piston assembly has the green cap. Backwash has great flow but then nothing for rapid rinse. Maybe I should just order a full new valve and start fresh.

 

[Reach4]

You could try setting the valve as I do for my H2S+iron filter, except set BD to 1. Plus choose your DO to a higher number probably.
-----------these are my settings-------------
DF GAL
VT dF1b
CT tc
NT 1
DO* 3
RT* 3:40 AM
BW 10
BD 4
RR 5
BF 0