Siemens RVD140-A šildymo/KVR valdiklis
- Purpose: single heating circuit + DHW control
- Series: Siemens Synco 100 (RVD digital controller family)
- Supply: 230V AC 50 Hz
- Inputs: outside, supply, DHW temperature sensors
Where Siemens RVD140-A is used
For multi-family substation control, commercial and administrative building central heating and domestic hot water (DHW) systems. The controller calculates supply temperature per an outside temperature compensation curve, controls the mixing/regulating valve (via 3-point control signal) and the circulation pump per day/night mode and weekly schedule. In DHW mode the controller regulates the primary side per the secondary DHW loop temperature setpoint.
Technical specifications
| Parameter | Value |
|---|---|
| Code | RVD140-A |
| Manufacturer | Siemens |
| Series | Synco 100 / RVD (digital controllers) |
| Application | 1 heating circuit + DHW (domestic hot water) |
| Supply | 230V AC ±10 %, 50 Hz |
| Power consumption | ~8 VA (verify in Siemens documentation) |
| Temperature sensors | Ni1000 / LG-Ni1000 (Siemens standard) |
| Heating circuit control | 3-point (open/close) mixing/control valve actuator |
| Pump control | Relay (on/off) for heating and DHW circulation pumps |
| Schedule | Weekly programming (day/night, weekends) |
| Compensation curve | Adjustable per outside temperature |
| Display | LCD with parameter and symbol view |
| Protection class | IP40 (indoor installation, control panel) |
| Ambient temperature | 0 → +50 °C |
Main control functions
- Outside temperature compensation heating curve: supply temperature is adjusted automatically per outside temperature (calculated from a tunable curve)
- Day/night mode: weekly programming with night setback — energy saving
- DHW production: primary side control per secondary DHW setpoint; priority selectable between heating and DHW
- Anti-legionella: periodic DHW temperature boost to eliminate bacteria
- Pump anti-seize kick: in summer the pump runs briefly once a week — prevents seizing
- Summer heating shutdown: automatic per outside temperature threshold
Compatible accessories and sensors
- Outside temperature sensor: Siemens QAC22 (Ni1000) or equivalent
- Supply/return temperature sensors: Siemens QAD22 (Ni1000 clamp-on)
- DHW temperature sensor: QAZ21 or QAP21.2 (immersion)
- Valve actuator: Siemens SSA/SSB series 3-point (e.g. SSB81 — 24V 3-point, also 230V versions available)
When to choose RVD140-A
- Multi-family substation refurbishment without BMS requirements
- Commercial building single heating loop + DHW systems
- Legacy RVD controller replacement keeping the same scheme
- When simple 230V supply without separate 24V sources matters
B2B delivery and logistics via Amegata.lt
- 24-hour delivery across the EU (from our warehouse in Vilnius)
- Competitive B2B pricing — often below market average
- 30-day payment terms for companies (per contract)
- Free technical consultation on controller selection and scheme
Official Siemens catalogue: siemens.com/hvac
Frequently asked questions
Is RVD140-A still in production?
The RVD series is being phased out for newer Siemens Synco 700 (RMH760 etc.) versions. Availability depends on Siemens supply chain — contact us, we will check real stock.
Can it be integrated with BMS (Modbus)?
Standard RVD140-A does not have Modbus/BACnet communication. For BMS integration choose Siemens Synco 700 (RMH760) with Modbus or KNX accessory. Alternatives — Ouman A203/C203 (with Modbus option) or Danfoss ECL 310.
How does RVD140-A differ from RVD145 or RVD230?
RVD140-A — 1 heating circuit + DHW. RVD145 — 2 heating circuits + DHW (combined radiator and underfloor). RVD230 — 2 heating circuits + DHW + additional functions. Choose per project requirements.
Can it be used without an outside temperature sensor?
Technically yes (a fixed supply temperature can be set), but uneconomical. Outside temperature compensation is the core RVD140-A value proposition, saving 15-25 % of energy versus fixed-temperature operation.
