Ouman VD220-2.5 two-way regulating valve, DN20, Kvs 2.5, PN 25, external thread
- Application: low-flow heating / DHW branch control
- DN + Kvs: DN20, Kvs 2.5 m³/h
- PN: PN 25
- Connection + media: external thread (ISO 228/1), water up to +130 °C
Where Ouman VD220-2.5 is used
VD220-2.5 is positioned as a low-flow regulating valve in Ouman substation automation. A Kvs of 2.5 m³/h fits heating branches up to roughly 30-45 kW (with ΔT 20 °C and a typical Δp of 0.2-0.5 bar). It is typically chosen for small radiator loops, DHW primary-side throttling in small multi-family buildings and process loops in individual substations.
The VD-series construction (red-metal / DIN 1705 body, ISO 228/1 thread) is designed for high temperatures and pressures — the Ouman catalogue specifies up to +130 °C and up to PN 25 (16-25 bar range). The valve closes with a spring; the control (turndown) ratio is 50:1.
Technical specifications
| Parameter | Value |
|---|---|
| Code | OMA0391 |
| Model | Ouman VD220-2.5 |
| Type | 2-way regulating valve |
| DN | DN20 |
| Kvs | 2.5 m³/h |
| Nominal pressure (PN) | PN 25 |
| Max closing Δp (with 300 N actuator) | up to 16 bar (0-1600 kPa) |
| Max operating Δp (with 400 N actuator) | up to 21.5 bar (0-2150 kPa) |
| Connection | External G-thread (ISO 228/1) |
| Media | Water, glycol solutions (up to 50 %) |
| Temperature range | up to +130 °C |
| Valve position | Spring-closed (NC — normally closed) |
| Stem stroke | 6.5 mm |
| Control (turndown) ratio | 50:1 |
| Leakage class | max 0.05 % (approx. class IV) |
| Body material | Red metal (DIN 1705) |
Flow calculation — Q = Kvs × √Δp
Flow through the valve is calculated as: Q = Kvs × √Δp (Q m³/h, Kvs m³/h, Δp bar).
Example: VD220-2.5 with Kvs 2.5 and loop Δp = 0.2 bar → Q = 2.5 × √0.2 ≈ 1.12 m³/h. At Δp = 0.5 bar → Q ≈ 1.77 m³/h. At Δp = 1 bar → Q = 2.5 m³/h (fully open valve).
Thermal capacity at ΔT 20 °C and Q = 1.12 m³/h: P = Q × ΔT × 1.163 ≈ 26 kW. At Q = 1.77 m³/h → P ≈ 41 kW.
When to choose Ouman VD220-2.5
- Low-flow radiator loop regulation in substations (up to ~30-45 kW)
- DHW primary-side throttling in small multi-family buildings
- When the project already uses an Ouman controller line (S203, EH-105, C203) and needs a compatible VD-series valve base
- Process loops in individual substations up to +130 °C, PN 25 class systems
- Actuator compatibility: Ouman M31A150 (OMA0205) or Ouman M31C150 (OMA0206) — standard package for heating / universal use; Ouman M41A15 (OMA0207) — when fast response or high Δp is needed (DHW branch).
B2B delivery and logistics via Amegata.lt
- 24-hour delivery across Lithuania (from our warehouse in Vilnius)
- Competitive B2B pricing — often below market average
- 30-day payment terms for companies (per contract)
- Free technical consultation on valve sizing and actuator selection
Official Ouman catalogue: oumanshop.com/VD220-2.5
Frequently asked questions
What is the maximum allowed Δp for this valve?
It depends on the paired actuator's force. With a 300 N actuator (Ouman M31A150 / M31C150) — closing Δp up to 16 bar (1600 kPa). With a 400 N actuator (Ouman M41A15) — operating Δp up to 21.5 bar (2150 kPa). In practice, substation loops rarely exceed 3-5 bar Δp, so a 300 N actuator is enough for standard designs.
Is it suitable for ethylene or propylene glycol solutions?
Yes — the red-metal body and spring-return stem are compatible with ethylene and propylene glycol solutions up to 50 % concentration. For DHW branches — only potable-grade fluids.
What mounting position is allowed?
Recommended: actuator vertical above the valve (actuator axis vertical, pointing up). Horizontal position is also allowed (actuator axis parallel to the floor). Do not mount the actuator below the valve — condensate can seep into the motor housing. Piping — any orientation.
Can Danfoss VRB 2 (DN20, Kvs 2.5) be used as a replacement?
As a functional analogue — yes (same DN20 / Kvs 2.5 / PN 25 class valve). But the mechanical adapter is not compatible — Danfoss VRB uses a different actuator interface than the Ouman VD series. If the project is fully in the Ouman ecosystem (controller, actuator), pick VD220-2.5; if in the Danfoss ECL line, pick Danfoss VRB 2 with an AMV actuator.
Are the valve and actuator sold separately?
Yes — Ouman VD-series valves are supplied without an actuator by default. Standard pairings: for heating — VD220-2.5 + M31A150 or M31C150; for DHW / high load — VD220-2.5 + M41A15. For Amegata.lt B2B customers we help select the right combination based on project Δp and thermal capacity.
