HERZ CAST IRON DOUBLE REGULATING & COMMISSIONING VALVES
The HERZ STRÖMAX-GF (VODRV Series) from HERZ Armaturen is a heavy-duty flanged double regulating and commissioning valve for precise flow control, differential pressure measurement, and shut-off in heating and cooling systems.
Manufactured from cast iron (EN-GJL 250) and available in PN16 and PN25 variants, the valve integrates two test points for differential pressure monitoring and a digital preset display for accurate flow adjustment.
Its non-rising spindle with a triple O-ring seal ensures smooth, maintenance-free operation, while the EPDM-coated seat provides tight sealing performance. The valve is ideal for balancing and commissioning large-capacity hydronic circuits in both commercial and industrial installations.
- 🔹 Type: Double regulating and commissioning valve (flanged)
- 🔹 Model Numbers: 4218 GF (PN16) / 4220 GF (PN25)
- 🔹 Body Material: Cast iron (EN-GJL 250, EN 1561)
- 🔹 Upper Part: Grey cast iron (DN50–DN300)
- 🔹 Spindle: Brass (DN50–DN100), stainless steel (DN125–DN500)
- 🔹 Sealing: Triple EPDM O-ring
- 🔹 Valve Cone: Cast iron, EPDM coated
- 🔹 Connection: Flanged (EN 1092-2)
- 🔹 Nominal Pressure: PN16 or PN25
- 🔹 Operating Temperature: -10°C to +110°C
- 🔹 Medium: Water and water-glycol mixtures (25–50%)
- 🔹 Flow Characteristic: Linear (BS 7350 compliant)
- 🔹 Test Points: 2 × ¼” measuring ports (HERZ 0284 series)
- 🔹 Display: Digital preset indicator
- 🔹 Coating: Lead- and chromate-free epoxy, ~100 μm thickness
- 🔹 Installation Orientation: Any (observe flow direction)
- 🔹 High-accuracy flow control and reproducible presetting.
- 🔹 Maintenance-free triple O-ring spindle sealing.
- 🔹 Corrosion-resistant construction for long service life.
- 🔹 Clear, tamper-proof digital preset display.
- 🔹 Compatible with HERZ differential pressure measuring devices.
- 🔹 Leak-tight, low-pressure loss performance.
- 🔹 Suitable for large-diameter pipe systems (DN25–DN500).
- 🔹 Hydronic HVAC systems (heating and chilled water).
- 🔹 District heating and cooling networks.
- 🔹 Industrial process water regulation.
- 🔹 Energy centers, risers, and distribution loops.
- 🔹 Commissioning and hydraulic balancing of building systems.
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