Parameters / Specifications Model: Fisher 289H‑41 Series: Fisher 289 Series Relief / Back‑Pressure Regulators Body Size / End Connections: 1″ NPT (inlet & outlet) for the “H” size version Relief (Set) Spring Range: Approx 1.0 to 4.5 psig (≈0.07 to 0.31 bar) for the “‑41” variant Maximum Allowable Inlet Pressure (Body Rating): Approx 100 psig (≈6.9 bar) for this body size Temperature Capability (depending on elastomer): Nitrile (NBR) / Neoprene (CR): –20 °F to +150 °F (≈ –29 °C to +66 °C) Fluoroelastomer (FKM): 20 °F to +300 °F (≈ –7 °C to +149 °C) (available on “H/HH” types) Approximate Weight: ~4 lb (≈2.0 kg) for the 1″‑NPT size “H” body Media / Application: Non‑corrosive gas or air service, used as a relief device or back‑pressure regulator in downstream systems to limit pressure, reduce pressure surges, protect equipment Features: Spring‑loaded throttling action with minimal pressure surge during relief Compact design for installation where space may be limited Reliable, relatively simple construction for high dependability
