Fleck 18022 - Seals and Spacer Kit 3150/3900 Upper Down Flow (DF)

The FL18022 seals and spacer kit renews the upper distributor seal set inside Fleck 3150 and 3900 downflow (DF) control valves, the point where water is directed cleanly into the resin bed rather than bypassing internally or leaking away to drain. WrekinWater supplies this genuine-fit kit to restore a full, tight seal in larger commercial and high-flow 3150/3900 systems.

Technical specifications

Symptoms that mean you need this part

• Water leaking continuously to drain even when the valve is in service position
• Softened water quality drops because untreated water is bypassing internally past worn seals
• Visible water seepage around the upper distributor or valve body joint
• Reduced flow or pressure through the softener despite the resin bed being in good condition

Why it fails / why it matters

The upper seal and spacer set forms the watertight barrier at the top of the distributor assembly in downflow 3150/3900 valves, keeping water flowing through the correct path into and out of the resin bed rather than short-circuiting internally. Under constant water pressure and the mineral content typical of hard water supplies, these rubber seals compress, harden and lose their sealing edge over time, allowing water to bypass internally or weep externally at the joint - both of which reduce softening performance and waste water to drain.

Why buy this from WrekinWater

WrekinWater has served more than 50,000 customers over 15 years and stocks Pentair Fleck, Autotrol, Clack, Kinetico and other major brands, so the FL18022 kit is supplied as genuine-fit parts sized correctly for the 3150/3900 upper downflow assembly. As a family run company based in Bettisfield, Shropshire rated Excellent on Trustpilot, we're happy to talk through fitment on larger commercial systems before you order.

How to fit it

1. Isolate the water supply to the valve and relieve pressure with a manual regeneration.
2. Disconnect the pipework and bypass fittings needed to access the upper distributor assembly.
3. Carefully separate the upper distributor from the valve body to expose the old seals and spacer.
4. Remove the worn seals and spacer, cleaning the housing and any grooves thoroughly.
5. Fit the new seals and spacer from the FL18022 kit, lightly lubricating rubber seals with a silicone-based lubricant.
6. Reassemble the distributor, restore the water supply, and check carefully for leaks or bypass before returning the system to service.