Siemens Acvatix™ range of globe valves, covering 2-way and 3-way valves for all applications — from small terminal units to large central plant systems, including zone, control, mixing, and industrial-grade valves.
Siemens Acvatix Globe Valves – Complete Summary
Acvatix is Siemens’ comprehensive HVAC valve range, optimised for energy efficiency, flexibility, and precise control. The globe valve portfolio is modular and classified by function, size, connection type, and control type.
🔹 1. Threaded Globe Valves (DN15–50)
Used in fan coils, VAV, reheaters, small air handlers
| Model | Type | Ports | Control | Pressure | Application |
|---|---|---|---|---|---|
| VVG41 | 2-way | 2 | On/Off, Floating | PN16 | General HVAC, basic control |
| VVX41 | 3-way | 3 | On/Off, Floating | PN16 | Mixing/diverting, terminal units |
| VVG44 | 2-way | 2 | Modulating | PN16 | Precision flow control |
| VVX44 | 3-way | 3 | Modulating | PN16 | Modulating mixing/diverting |
| VVG44.K | 2-way | 2 | Modulating + Kvs Pre-setting | PN16 | Balancing & control combined |
| VVI46 | 2-way | 2 | On/Off (zone) | PN16 | Terminal units, compact zones |
| VXI46 | 3-way | 3 | On/Off | PN16 | Mixing/diverting in small circuits |
| VVP45 | 2-way | 2 | On/Off (preassembled) | PN10 | Thermal actuator included |
| VXP45 | 3-way | 3 | On/Off (preassembled) | PN10 | Compact zone valve w/ actuator |
🔹 2. Flanged Globe Valves (DN65–150)
Used in central plant systems (chillers, boilers, AHUs)
| Model | Type | Ports | Control | Pressure | Application |
|---|---|---|---|---|---|
| VVG55 | 2-way | 2 | Modulating | PN25/PN40 | Large HVAC water systems |
| VVX55 | 3-way | 3 | Modulating | PN25/PN40 | High-capacity mixing or diverting |
🔹 3. Industrial & High-Performance Globe Valves (VD.. Series)
Used in district heating, high temp/pressure, steam, and aggressive media
| Model | Body Type | Ports | Pressure | Material | Use Case |
|---|---|---|---|---|---|
| VDN | Flanged | 2 | PN16 | Cast iron | General purpose |
| VEN | Flanged | 2 | PN25 | Ductile iron | High-pressure HVAC |
| VUN | Flanged | 2 | PN40 | Steel | Steam and district heating |
| VVF/VXF | Flanged | 2/3 | PN25–40 | Ductile iron | Precise control in plants |
| VXG | Flanged | 3 | PN16–40 | Cast iron | Mixing valves, industrial |
🔹 4. Special Features Across the Range
| Feature | Available In |
|---|---|
| Kv pre-setting | VVG44.K, VVI/VXI series |
| Internally threaded (Rp) | VVG/VVX/VVI/VXI/VVP/VXP |
| Flanged (PN25/PN40) | VVG55/VVX55/VDN/VEN/VUN |
| Modulating control | VVG44, VVX44, VVG55, VD.. |
| On/Off / Thermal actuators | VVI, VXI, VVP, VXP |
| Actuator options | SFA, STA, SFP (thermal); SAX, SKD, SKB, SKC (electronic) |
Actuator Compatibility Overview
| Valve Series | Typical Actuators | Control Type |
|---|---|---|
| VVP/VXP | SFP… (built-in) | On/Off |
| VVI/VXI | STA, STP, SFA, SFP | On/Off / Thermal |
| VVG41/VVX41 | STA, STP, SAX… | On/Off / Floating |
| VVG44/VVX44 | SAX, SKD, SKB, SKC | Modulating |
| VVG55/VVX55 | SKB, SKC, GQD, SQX | Modulating |
| VD../VXG/VVF/VXF | SKD, SKB, SKC, electric rotary | Modulating / 3‑pt |
When to Use What
| Use Case | Recommended Valve |
|---|---|
| Small fan coils | VVP45 / VVI46 + SFA |
| Reheat coils, VAVs | VVI46 / VVG41 |
| Precise room control | VVG44 + modulating actuator |
| Mixing in zone system | VXI46 / VVX44 |
| Large AHU chilled/hot water loop | VVG55 / VVX55 |
| High-temp steam | VUN + SKC actuator |
| District heating or PICV setup | VVG44.K |
MORE INFORMATION ON 2 WAY GLOBE SELECTION;
VVG41 – 2-Way Control Valve (Standard Range) 
- Type: 2-way valve
- Control: Typically on/off or floating control
- Operation: Designed for use with thermal or electro-mechanical actuators
- Application: General HVAC water systems – chilled or heating water
- Connection: Internally threaded (usually Rp thread)
- Body Material: Often bronze or brass
- DN Sizes: Commonly DN15 to DN50
- Pressure Rating: PN16 or similar
VVG44 – 2-Way Control Valve (High-Performance Range) 
- Type: 2-way valve
- Control: Designed for modulating control
- Operation: Paired with electronic modulating actuators (e.g., SAX, SKD/SKP)
- Application: More precise flow control needed – typically used in systems requiring accurate temperature regulation
- Connection: Also usually internally threaded
- Body Material: Higher-grade materials (often bronze or special alloys)
- Flow Characteristic: Often equal percentage
- Pressure Rating: Higher precision, may have tighter leakage rates and stroke tolerances
| Feature | VVG41 | VVG44 |
|---|---|---|
| Valve type | 2-way | 2-way |
| Control | On/Off or Floating | Modulating |
| Actuator type | Thermal, electro-mechanical | Modulating electronic |
| Application | Basic HVAC | Precision HVAC control |
| Flow characteristic | Linear or not specified | Equal percentage (better control) |
| Use with… | STA/STP actuators | SAX/SKD/SKP actuators |
