Danfoss RAS-C2 Built-In Sensor 13 g, Radiator Thermostatic Sensor, TRV Sensor Insert, Thermostatic Control Sensor, Valve Sensor Cartridge

Radiators and accessories covers the heat emitters for central heating and electric heating: panel radiators, column and designer radiators, heated towel rails, and portable or wall-mounted electric heaters, along with the parts that go with them.

Heat output

Radiator and towel rail outputs are published in watts, tested to BS EN 442 at a Delta T of 50. That means a mean water temperature of 70°C in a room at 20°C, so outputs from different makers can be compared like for like. If your system runs cooler, as with a heat pump or a boiler set to a low flow temperature, the radiator gives out less: at Delta T 40 the output is roughly three quarters of the Delta T 50 figure.

Choosing a style

• Panel radiators: made in a wide range of heights and lengths.
• Column and designer radiators: vertical, horizontal and curved shapes. Check the output, not just the size.
• Towel rails: for bathrooms and kitchens, in chrome, white and other finishes. Some run on the central heating only, others on electricity, so check which type you need.
• Electric heaters: oil-filled and oil-free column heaters and panel heaters, some with timers.

Regulations and installation

In England, Approved Document L expects any new radiator on a wet heating system to have a thermostatic radiator valve, unless it is in the room with the main room thermostat. Wiring in a fixed electric towel rail or heater can be notifiable under Part P of the Building Regulations, particularly for a new circuit or in a bathroom, and must then be done by a registered competent person or notified to building control.

For valves, see thermostatic radiator valves; for thermostats and programmers, see heating controls.