Seko Non-Return Injection Valve 3/8"–1/2" PP

Seko Non-Return Injection Valve for Dosing Pumps — Part No. 9900108527

The Seko non-return injection valve 9900108527 is the genuine OEM replacement fitting that connects the dosing pump outlet hose to the pool's main pipework. Its integrated non-return mechanism serves two critical functions: it allows precise injection of the chemical product (chlorine, pH-minus, pH-plus, algaecide) into the filtration circuit, and it prevents backflow of pressurised pipe water into the pump — protecting the internal mechanism and avoiding cross-contamination.

Technical specifications

• Manufacturer part no.: 9900108527
• Supplier ref.: 01006126
• Brand: Seko (genuine OEM part)
• Material: Polypropylene (PP) — chemical and corrosion resistant
• Main thread: 3/8" male BSP gas thread
• Adapter included: M-1/2" to F-3/8" (universal fit)
• Non-return function: Yes — prevents backflow into the pump
• Compatibility: Compatible with most peristaltic dosing pumps on the market

How the non-return injection valve works

This fitting is the final link between the dosing pump and the pool water. It is installed directly into the filtration pipework at the chemical injection point. The built-in non-return valve opens automatically under the pump's discharge pressure and snaps shut the instant the pump stops, preventing pressurised pipe water from flowing back into the dosing circuit. This safeguards the santoprene tube, the rollers and all internal pump components, significantly extending the pump's service life.

When to replace it

Inspect the injection valve at the start of each pool season. Signs that replacement is needed: dripping or moisture around the injection point, inconsistent dosing despite the pump running normally, or visible water backflow into the pump when it is switched off.

What's in the box

1× Seko non-return injection valve, polypropylene — Part no. 9900108527.
1× M-1/2" to F-3/8" adapter included.
Recommended companion part: Seko santoprene membrane tube RIC0152552.