Smart radiator valves adjust temperature per room based on time and your presence. Instead of setting everything to one fixed temperature, they reduce at night or when you're away, automatically. This saves 10–15% without comfort loss.
Step by step
A smart thermostat head measures room temperature and adjusts the valve opening ratio. With programmed schedules it can for example run at 16 °C nights (10 PM–6 AM) and 20 °C mornings (6 AM). Special models also detect when you're away (via phone location) and lower temperature. Your central heating needs to pump less hot water through radiators, that saves gas or oil.
Source: Stiftung Warentest 11/2023, Smart radiator thermostats pay for themselves in 2–3 years
Step by step
- Check your radiator valve typeLook at the top of your radiator: is there a thermostat head (cylindrical, with scale)? Smart heads fit the same base, but with an electric motor. Measure the diameter: M30 × 1.5 mm is standard.
- Choose a beginner-friendly systemAs a beginner: do yourself a favor and pick a set from one brand (like tado, Eve, Bosch, Danfoss). These systems have a central app and work together. Cost per room: €60–120, with hub: +€50–80.
- Install bridge / hubMost systems need a central hub device (often connected to heating or in the kitchen) to communicate with your WiFi. Costs €50–100 extra, but it's required for full automation.
- Replace old headsTurn the radiator thermostats counterclockwise until off (releases old head), swap the heads out (takes ~2 minutes per radiator). Turn the new heads back on.
- Program the appOpen the system app, register all rooms/radiators and set schedules: weekly plan with different times for work and rest days. After 1 week of optimization the system runs automatically.
Worked example
Before: 3-room old building with manual thermostats, all set to level 3 (about 20 °C). Resident forgets to lower at night, works away during day, doesn't adjust temperature. Heating costs €1,800/year.
After: Smart thermostats in all 3 rooms (costs: €400). Schedule: nights 16 °C, Mon–Fri 6–8 AM and 6–11 PM at 20 °C, otherwise 17 °C. Weekends: 8 AM–10 PM at 20 °C. System optimizes fuel use → 12% savings (about €216/year). Pays for itself in 1.8 years.