WAR non-return valves provide a practical way to protect drainage systems against backflow while also helping to prevent rodents and other vermin from entering a property through drainage pipework. Available from IPS Flow Systems in 4-inch and 6-inch sizes, the WAR range is designed for use in drainage applications where backflow, flooding, pest ingress or maintenance access needs to be controlled. The valves can be used with both clay and plastic pipes, making them suitable for a wide range of existing and new drainage installations.
What Is a WAR Non-Return Valve?
A WAR non-return valve is a one-way drainage valve designed to allow wastewater and effluent to travel in the normal direction of flow while preventing it from returning through the pipe. This is particularly important where a drainage system may be exposed to backflow during flooding or surcharge conditions. By closing when flow reverses, the valve provides a physical barrier between the downstream drainage system and the property it is protecting. The WAR valve also incorporates features specifically intended to help prevent rodents and other vermin from travelling through drainage pipework.
How Do WAR Non-Return Valves Work?
During normal operation, wastewater flowing in the intended direction pushes the valve flap open and passes through the unit. Once the flow has passed, the flap returns to its closed position. If the direction of flow reverses, the pressure acts against the flap rather than opening it. This keeps the valve closed and helps prevent effluent from flowing back towards the property.
The same flap also creates a physical barrier against rodents and other vermin attempting to travel upstream through the drainage system.
Key Features and Benefits of WAR Non-Return Valves
WAR non-return valves combine backflow protection with a number of features designed
for drainage, pest-control and maintenance applications.
- Stops backflow of effluent: The valve helps prevent effluent from backing up into
homes, businesses and other properties during flooding. WAR valves are used
extensively in properties situated on flood plains. - Rodent and vermin protection: The closed flap provides a barrier against rodents
as well as frogs, snakes and other vermin entering a property through the drainage
system. - Stainless steel reinforced flap: An inbuilt stainless steel plate reinforces the flap
and helps prevent rodents from biting through it, providing an additional level of
pest protection. - Helps prevent noxious fumes: As well as controlling backflow and vermin ingress,
the valve helps prevent noxious fumes from entering a property through the
drainage system. - Lockable flap: The flap can be locked to close an entry pipe to an inspection
chamber, providing useful isolation while essential drainage maintenance is carried
out. - Reusable for maintenance applications: When used as a temporary maintenance
measure, the valve can be inserted while work is taking place and then removed for
reuse elsewhere. - Funnel-shaped body design: The WAR valve uses a funnel-shaped body designed
to increase the flow of water as it passes through the unit, helping to reduce the risk
of blockages. - Fits clay and plastic pipes: Compatibility with both pipe types makes WAR valves
suitable for a variety of drainage systems, including many existing installations. - 5-year guarantee: WAR non-return valves are supplied with a five-year guarantee.
Applications for WAR Non-Return Valves
WAR non-return valves can be used wherever there is a requirement to control reverse flow or unwanted access through drainage pipework. Typical applications include homes and commercial premises exposed to flood or backflow risk, properties requiring additional protection against rodents and vermin, drainage maintenance work and environments where preventing drainage odours and fumes is particularly important.
Flood and Backflow Protection
During flooding or other conditions that cause downstream drainage levels to rise, effluent can potentially travel back through connected drainage pipework towards a property. A WAR non-return valve provides a one-way barrier designed to stop this reverse flow while continuing to permit normal drainage in the intended direction. This makes the valve particularly relevant for properties in flood-prone locations and other installations where drainage backflow has been identified as a risk.
Rodent and Vermin Protection
Drainage systems can provide a route into buildings for rats and other unwanted pests. The WAR valve’s flap creates a physical barrier within the pipe, while the inbuilt stainless steel plate helps prevent rodents from biting through it.
In addition to rodents, the manufacturer identifies the valve as providing protection against frogs, snakes and other vermin entering homes, businesses and other properties through drainage pipework.
Drainage Maintenance
The lockable flap also makes the WAR valve useful during drainage maintenance. An entry pipe to an inspection chamber can be closed while essential work is carried out, helping to isolate the relevant section. For temporary maintenance applications, the valve is reusable. It can be installed while the work is undertaken, removed afterwards and retained for subsequent use.
Food and Catering Environments
WAR non-return valves can help prevent noxious fumes from travelling back through drainage pipework into a property. This characteristic makes them particularly relevant to food and catering environments, where drainage conditions and unwanted odours can create operational and hygiene concerns. The appropriate drainage solution should always be selected with the complete application and installation conditions in mind.
WAR Non-Return Valve Sizes
IPS Flow Systems offers WAR (Water and Rodent) non-return valves in two sizes: 4 inch and 6 inch. Selecting between them should be based on the drainage pipework and the dimensions and configuration of the installation rather than simply choosing a nominal valve size.
4 Inch WAR Non-Return Valve
The 4-inch WAR non-return valve provides the same combination of one-way flow, backflow prevention and vermin protection for compatible 4-inch drainage installations. The 110mm/4 inch valve is WRc tested and certified. Its universal fit design allows installation to straight and bent inlets. Before specifying the valve, the existing pipe material and actual internal dimensions should be checked to confirm suitability, particularly when retrofitting into existing drainage infrastructure.
6 Inch WAR Non-Return Valve
The 6-inch WAR non-return valve provides the equivalent functionality for larger compatible drainage pipework. As with the 4-inch model, the installation should be assessed for pipe material, internal dimensions, access, flow direction and sufficient space for the flap to operate correctly. IPS can provide product selection support where the required valve size or compatibility with existing pipework needs to be confirmed.
Clay and Plastic Pipe Compatibility
WAR non-return valves are suitable for use with both clay and plastic pipes, giving installers and maintenance teams flexibility when working with different drainage systems. Pipe compatibility should, however, be considered as part of the overall specification. Nominal pipe size alone does not necessarily provide all the information required for correct product selection. The pipe material and relevant internal dimensions should be checked, particularly on existing or older drainage systems where dimensions and configurations may vary. For retrofit applications, it is also important to consider the condition of the existing pipe, available access and whether the installation provides sufficient clearance for unrestricted valve operation and future inspection.
WAR Non-Return Valve Installation and Retrofit Considerations
A WAR non-return valve may provide a relatively straightforward means of adding backflow and vermin protection to suitable drainage pipework, but correct product selection and installation remain important. Before installation, the required valve size should be confirmed against the pipe material and relevant internal pipe dimensions. The direction of normal drainage flow must also be identified so that the valve operates in the correct orientation. The installation location should provide suitable access, typically through an appropriate inspection chamber or other accessible drainage point. There must be adequate clearance for the flap to open freely during normal flow and close without obstruction. Future maintenance should be considered at the same stage. The valve should remain accessible for inspection, cleaning and checks of flap movement rather than being positioned where routine access becomes difficult. All installations should follow the manufacturer’s current installation requirements. Where the existing drainage arrangement or correct valve selection is uncertain, the application should be reviewed before installation.
Maintaining a WAR Non-Return Valve
Like other mechanical components installed within a drainage system, a WAR non-return valve should remain accessible for periodic inspection. Maintenance should include checking for accumulated debris or material that could interfere with the valve and confirming that the flap can move freely between its open and closed positions. The condition of the valve and flap should also be inspected as appropriate for the application.
Providing suitable access when the valve is first installed makes these checks easier and helps ensure that the valve can be inspected and maintained without unnecessary disruption to surrounding drainage infrastructure.
Choosing the Right WAR Non-Return Valve
Correct selection starts with understanding the drainage system and the reason protection
is required. Before selecting a WAR non-return valve, consider:
- Pipe size
- Pipe material
- Application
- Flood and backflow risk
- Rodent protection requirements
- Installation configuration
- Available access and flap clearance
- Future maintenance requirements
Where an application is unusual or the existing drainage system is uncertain, IPS Flow Systems can provide technical input to help identify the appropriate product and confirm the key selection considerations before ordering.
WAR Non-Return Valves from IPS Flow Systems
IPS Flow Systems supplies WAR non-return valves alongside its wider drainage and flow-
control offering. Our approach goes beyond supplying an individual component. IPS works with customers to understand the application and support appropriate product selection, with technical knowledge available to help address specification, installation and maintenance considerations. Whether you are protecting an existing property against backflow, addressing rodent ingress or planning drainage maintenance, discussing the pipework and application requirements before ordering can help ensure that the correct solution is selected.
Speak to IPS About WAR Non-Return Valves
Need help selecting a 4-inch or 6-inch WAR non-return valve?
Speak to the IPS Flow Systems team about your drainage application, pipe material, dimensions and installation requirements. We can help you review the application and select the appropriate WAR valve for your system.
Contact IPS Flow Systems to discuss WAR non-return valves and drainage protection.
FAQs
What does a WAR non-return valve do?
A WAR non-return valve allows wastewater and effluent to flow in the intended direction while helping to prevent reverse flow back towards a property. It can provide protection against backflow during flooding while also helping prevent rodents, vermin and noxious fumes from entering through drainage pipework.
Do WAR non-return valves help prevent rodent entry?
Yes. WAR non-return valves are designed to prevent rodents and other vermin from travelling through drainage pipework into a property. The flap incorporates a stainless steel plate designed to prevent rodents from biting through it.
What sizes of WAR non-return valve are available?
IPS Flow Systems offers WAR non-return valves in 4-inch and 6-inch sizes. The appropriate size should be selected according to the drainage pipework and installation requirements.
Can WAR non-return valves be used with clay and plastic pipes?
Yes. WAR non-return valves are suitable for both clay and plastic pipes. The pipe material and relevant dimensions should be checked before selection and installation to ensure the valve is appropriate for the particular drainage system.
Can WAR non-return valves be retrofitted to an existing drainage system?
WAR non-return valves can be suitable for retrofit applications where the existing drainage system provides the correct pipe dimensions, orientation and suitable access. Before specifying a valve, the pipe size and material, internal dimensions, direction of flow, available flap clearance and maintenance access should all be checked. IPS can provide technical product selection support where compatibility needs to be confirmed.
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