Radiator Thermostats & TRVs | Manual and Smart Thermostatic Radiator Valves

A thermostatic radiator valve — or TRV — is one of the simplest and most cost-effective upgrades you can make to a wet central heating system. Fitted in place of a standard radiator valve, a TRV controls the flow of hot water into each individual radiator based on the temperature of the room around it. When the room reaches your desired temperature, the valve closes and stops the radiator heating further. When it cools down, it opens again. The result is that each room maintains a comfortable, consistent temperature without you having to manually adjust anything — and without wasting energy heating rooms that are already warm enough.

Manual TRVs vs Smart TRVs — What's the Difference?

A manual TRV has a numbered dial (typically 1–5) that you set once and leave. It's mechanical, battery-free, and entirely self-contained. These are a reliable, no-fuss option that suit most homeowners and are perfect for rooms that tend to stay at a predictable temperature. Our Reina Modal range covers this category, available in a wide range of finishes including chrome, anthracite, black, white, brushed, and bronze — in straight, angled, and corner configurations to suit any radiator installation.

A smart TRV replaces the manual head with a programmable, app-controlled or wireless unit that gives you precise scheduling, remote control via your phone, and often integration with your wider smart heating system. These are ideal if you want room-by-room control from anywhere, want to set heating schedules per room, or are building out a multi-zone smart heating setup. Our smart range includes options from Hive, Honeywell Evohome, Salus iT600, EPH Ember, and ENGO Controls — each compatible with their respective smart heating ecosystems.

What to Check Before Buying

The most important compatibility consideration is the valve body connection size — most UK radiators use an M30 × 1.5mm thread, which is the most common standard, but some older radiators (particularly those with Danfoss RA-type valve bodies) require an adapter. Smart TRVs in our range that need this will include or offer a compatible adapter — check the individual product listing if you're unsure.

It's also worth knowing that a TRV controls only the individual radiator it's fitted to — it doesn't control your boiler or heating pump. For best results, TRVs work alongside a main room thermostat or smart thermostat that manages when the boiler fires. One room in your home (typically the hallway or living room) should always have a standard thermostat rather than a TRV, to ensure the boiler always has a reference point to work from.

Browse our full range of manual and smart thermostatic radiator valves below, or contact our team if you need help choosing the right TRV for your system.