BELIMO R639AS+SRF24A-SR-5

The Belimo R639AS+SRF24A‑SR‑5 combines a rugged 2‑way control valve body with a powerful modulating rotary actuator, offering a turnkey solution for fluid and steam control in HVAC, hot‑water, steam, or hydronic systems. Whether you are managing heating loops, steam distribution, boiler control, or high‑temperature water circuits in commercial buildings or industrial installations — this unit ensures reliable, automated regulation.

With a high temperature rating up to 175 °C and a flow coefficient of 34.5 m³/h, the valve supports high‑demand heating and steam applications. The modulating actuator (24 V AC/DC, 2–10 V control) allows smooth proportional control of flow — not just on/off — enabling precise temperature or pressure control and better energy efficiency. The extremely low leakage rate (≤ 0.01% Kvs) ensures near bubble‑tight shut‑off, which is critical for steam or high‑pressure water systems to prevent wastage or pressure loss.

The actuator is IP54‑rated and fail‑safe (closed on power loss), offering protection against dust and splash — suitable for boiler rooms, plant rooms, mechanical spaces or other challenging environments. Compared to manual valves or mismatched valve‑actuator combos, this Belimo set offers a professionally matched, high‑reliability package with minimal maintenance, better safety, and consistent performance — saving time during installation and reducing long‑term operation risk. Belimo+1