EA-class anti-contamination check valve, 1 1/2 inch, internal-external thread RV277-11/2A

Protection of Potable Water Installations Against Backflow

When installing pressure regulators, filters, or reduction-filtration stations, it is crucial to ensure that water from the internal installation does not flow back into the water supply network. The anti-contamination check valve, class EA (model RV277-11/2A), serves as an independent safety device meeting the requirements of standard EN 1717 for category 2 devices. Its primary function is to prevent contamination of potable water in central supply systems, which is particularly important in locations where backflow risk exists due to pressure drops in the network or vacuum conditions.

The device features a simple and direct construction, facilitating integration with existing installations. Thanks to the use of dezincification-resistant brass (DZR) in the housing and EPDM monomeric rubber seals, the valve is suitable for potable water at temperatures ranging from 2 to 65 °C. These materials comply with guidelines for contact with drinking water, ensuring safe operation. Notably, the valve holds a DVGW certificate for water, confirming its suitability for sanitary installations.

Key Construction Features and Operating Parameters

The valve is designed to minimize flow resistance and avoid noise generation or hydraulic shocks during operation. Its construction is based on a conical mechanism with a closing spring, ensuring rapid and tight closure upon flow cessation or direction change. The valve's opening pressure is only 10 mbar, meaning it responds very sensitively to even minor pressure changes, effectively blocking water backflow.

For installers, ease of installation is also important due to the specific connection arrangement: a 1 1/2 inch (40 mm) BSPT tapered external gas thread on the inlet transitions to a 2 inch (40 mm) internal thread on the outlet. This solution allows direct connection to various installation components without the need for additional adapters. The device has compact dimensions with a total length of approximately 104 mm, enabling installation even in limited technical spaces. Structural durability is ensured by pressure class PN 25, allowing operation at a maximum working pressure of up to 25 bar at 20 °C. The flow coefficient Kvs is 41 m³/h, indicating low hydraulic resistance even at high flow rates.

Application and Operating Conditions

The RV277-11/2A valve is widely used as an additional safety element downstream of reduction-filtration stations, as well as mechanical and carbon filters. It is a universal solution, suitable for both larger-diameter domestic water supply installations and public facilities or industrial water supply systems. Due to its low pressure loss (low pressure drop), it does not negatively affect the performance of the entire installation even at high flow rates.

The manufacturer provides a 5-year warranty from the date of production, which is an additional advantage when selecting this model in the anti-contamination valve market. It should be noted that this device is not intended for CO water or chemically aggressive media other than potable water meeting sanitary standards. Installation must be carried out in accordance with the manufacturer's instructions, ensuring proper thread tightening and sealing of connections to avoid leaks under high working pressure. Thanks to its simple construction and high material reliability, this valve provides a durable solution to the problem of backflow in modern hydraulic installations.