B27 - 22mm check Valve (Non Return Valve NRV)

The B27 is a 22mm non-return (check) valve from the Aquamatic range, fitted inline on water softener and filtration pipework to stop water flowing backwards through the system. WrekinWater supplies it as a direct replacement where an existing 22mm NRV has failed or perished, keeping your installation compliant and leak-free. It's a small part, but an important one for protecting your mains supply from contamination.

Signs you need this part

• Water or brine appears to be moving backward through the softener outside a normal regeneration cycle.
• Treated water occasionally tastes or smells of brine when it shouldn't.
• A drip or weep is visible from the valve body itself, rather than a pipe joint.
• The old valve is cracked, discoloured or its flow-direction arrow has worn away after years in service.

A check valve like the B27 uses a small spring-loaded disc that lifts to let water pass one way and seats shut to stop it going the other. Constant pressure cycling and years of flow can weaken that spring or perish the seal, letting water creep back the wrong way. On a softener installation, a failed non-return valve can allow softened or brine-laden water to siphon back toward the mains side, which is exactly what the valve is there to prevent.

WrekinWater is a family run business based in Bettisfield, Shropshire, that has served more than 50,000 customers over 15 years and is rated "Excellent" on Trustpilot. We stock genuine Aquamatic fittings alongside major valve brands like Pentair Fleck, Autotrol, Clack and Kinetico, so you can order the exact part your system needs.

How to fit it

1. Turn off the water supply and open a nearby tap to relieve pressure in the pipework.
2. Cut out the section of 22mm pipe containing the old check valve.
3. Deburr the pipe ends and dry-fit the new B27, making sure the flow-direction arrow matches your water flow.
4. Connect the valve into place using the same joint method as your existing pipework.
5. Turn the water supply back on and check both joints closely for leaks.
6. Run the softener through a short cycle to confirm normal flow with no backflow.