FISHER 289H-43 relief Valves or Backpressure Regulators

The FISHER 289H-43 is part of the 289 series of pressure relief valves or back pressure regulators, which are described below:

Connection Size: FISHER 289H models are available with NPT threaded connections in 1NPT and 2NPT sizes for easy installation and removal with a wide variety of piping systems.

Pressure Parameters

Maximum Allowable Pressure Relief (Inlet) Pressure: Typically, the FISHER 289 series is 100 psig/6.9 bar, but the 289H model is unique in that it has a maximum pressure relief (inlet) pressure of 25 psig/1.7 bar.

PRESSURE RELIEF SET PRESSURE RANGE: The pressure relief set pressure range for the FISHER 289 series is generally 5wc to 50psig (25mbar to 3.5bar), and for the 289H-43 models, this range can be referenced for the time being, unless otherwise specified, but may vary depending on the actual requirements and spring settings.

Temperature range: -20 to 150°F (-29 to 66°C) with Nitrile (NBR) and Chloroprene (CR) seals; 20 to 300°F (-7 to 149°C) with Fluorocarbon (FKM) (Models 289H and 289HH only).

Weight: 4lb/2kg for 1NPT, 15lb/7kg for 2NPT.

Other Features: The FISHER 289 series pressure relief valve is a spring-loaded, throttled pressure relief valve with a large valve diaphragm area and high sensitivity, making it ideal for low-pressure settings. Its smooth throttling operation minimizes pressure shock in the system during relief operation. However, this series of pressure relief valves is designed for pressure control and is not suitable for use as an ASME safety relief valve.