Fleck 2850 DLFC (Drain Line Flow Controllers) Fleck parts 25171 and 25581

WrekinWater stocks the Fleck 2850 Drain Line Flow Controller (DLFC), covering Fleck parts 25171 and 25581, a genuine Pentair Fleck component that regulates backwash and rinse flow to drain during regeneration on a 2850 valve, keeping water and salt usage on target.

Technical specifications

Symptoms that mean you need this part

• Regeneration cycles running noticeably faster or slower to drain than they used to
• Higher than normal water or salt consumption during regeneration
• Cloudy or discoloured water after regeneration, suggesting the resin bed isn't rinsing properly
• Visible cracking, wear or debris blocking the DLFC button when the drain fitting is inspected

Why it fails / why it matters

The DLFC is a precisely sized flow restrictor that controls exactly how much water passes to drain during backwash and rinse, so the resin bed gets the right contact time without wasting water or salt. Grit, scale or general ageing of the plastic insert can partially block or distort the opening, which throws off the drain flow rate and either shortens the rinse (leaving resin under-cleaned) or lengthens it (wasting water).

Why buy this from WrekinWater

WrekinWater has supplied genuine Fleck components to more than 50,000 customers over 15 years from our base in Bettisfield, Shropshire, and stocks Pentair Fleck alongside Autotrol, Clack, Kinetico and other major brands, so we can match the correct DLFC rating to your 2850 valve setup. We're UK Company No. 11000488, rated "Excellent" on Trustpilot.

How to fit it

1. Isolate the softener at the inlet and relieve system pressure before starting
2. Locate the drain line fitting on the valve body where the DLFC insert is housed
3. Unscrew or unclip the drain fitting to access the old DLFC button
4. Remove the old DLFC and check for cracking, debris or wear against the new part
5. Fit the new DLFC into the drain fitting, making sure it's seated fully and the fitting is reassembled securely
6. Restore the water supply and run a manual regeneration cycle to confirm the drain flow rate looks correct and there are no leaks