22mm non return valves are a key component in plumbing and heating systems, designed to allow fluid to flow in one direction only. By preventing reverse flow, they help protect equipment, maintain water quality, and ensure your system runs efficiently without contamination or pressure disruptions.These valves are compact, easy to install, and compatible with standard 22mm pipework, making them a perfect fit for both domestic and light commercial applications. Whether used in central heating circuits, hot water systems, or mains-fed supplies, a non return valve helps maintain correct directional flow and safeguards against backflow that could damage pumps, valves, or other components downstream.

Key features and benefits of 22mm Non Return Valves.

Key Features

Prevents reverse flow of water, helping to protect appliances and maintain system integrity. Ideal for maintaining directional control in hot water, cold water, and heating systems.

Key Features

The slim profile fits neatly into tight pipe runs and confined spaces. Perfect for under-sink setups, cylinder feeds, or concealed pipework.

Key Features

Protects against contamination from dirty or stagnant water entering the clean water supply. Essential for compliance with water regulations and safe system operation.

Key Features

No manual intervention required — the valve opens and closes automatically based on flow direction. This ensures constant protection without user input or monitoring.

Key Features

Designed to minimise water hammer and flow noise during operation. Ideal for residential settings where silent performance is preferred.

Key Features

Constructed from durable materials like brass or stainless steel to withstand corrosion and scale build-up. This ensures long-term reliability even in demanding water conditions.

22mm non return valves play a crucial role in system protection, especially in setups where water must only move in one direction. In heating and domestic water systems, uncontrolled backflow can result in contamination, increased wear on components, or malfunction of pumps and pressure valves. Installing a non return valve eliminates these risks by ensuring that flow is automatically stopped if it tries to reverse direction.

They’re also a vital part of compliance in certain systems, helping to meet water safety regulations and prevent cross-connection issues. With their compact size and reliable design, 22mm non return valves offer a simple but highly effective solution for maintaining clean, efficient water flow.

You’ll commonly find 22mm non return valves installed on central heating return lines, unvented cylinder feeds, and cold water mains supplying combi boilers or electric showers. They're also used in pump systems to maintain prime and avoid back-pressure damage.

In domestic properties, they're often fitted in-line under sinks, behind appliances, or before check valves in sealed systems. In commercial settings, they help protect equipment in plant rooms and water distribution networks. Their compatibility with standard 22mm pipework makes them a go-to solution for both new installations and retrofits where backflow must be prevented.

It allows water to flow in one direction only, automatically preventing reverse flow in your system.

In-line with pipework feeding water heaters, pumps, or mains supply points to prevent backflow.

Check Valves work by using a swinging or lifting mechanism to allow fluid to flow in one direction while automatically closing to prevent backflow. When fluid flows in the desired direction, the valve opens, and when there is reverse flow, it closes to block the flow.

Yes, most models can handle both hot and cold water within the recommended temperature limits.

Many non return valves are designed for both orientations, but always check the flow direction and manufacturer’s guidance.

The valve closes automatically, blocking the reverse flow and protecting downstream components.

They’re essentially the same — the terms are often used interchangeably in plumbing.

Yes, it’s common to fit a non return valve on the cold feed to a combi boiler to prevent cross-contamination.

Yes, 22mm non return valves are available in compression or push-fit versions for quick installation.

They are generally maintenance-free but may require inspection if you notice unusual flow issues.

A slight pressure drop may occur, but full-bore models minimise flow restriction effectively.

With normal use, a quality 22mm non return valve can last several years with minimal wear.

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