Danfoss

Look at how your pipe meets the radiator: choose an angled valve when the pipe comes up from the floor or out of the wall at 90 degrees to the radiator, and choose a straight valve when the pipe runs directly along the wall into the radiator. Angled valves save space where the pipe joins from below; straight valves give a neater run-in where pipes are in-line behind or beside the radiator. For example, if your pipe rises from the floor beneath a living‑room radiator, an angled RAS‑C2 or RAS‑D2 will fit without awkward bends.

Match the valve bore to the copper pipe feeding your radiator: 15mm is the most common size for UK radiator installations and is listed across the Danfoss range here, while 10mm is used on smaller-bore runs or older systems. If you are unsure, take a simple measurement of the pipe outside diameter or check your existing valve marking; many product listings also offer packs that include both 10mm and 15mm options to cover uncertainty. Buying the correct size avoids leaks and gives the right flow through the radiator.

The RAS‑C2 range includes lower-cost white valves in both angled and straight forms and common single-size items, while the RAS‑D2 range appears as a higher-priced option with chrome finishes and pack configurations. If the valve will be highly visible in a kitchen or bathroom, the D2 chrome gives a polished look; the C2 white is a solid, discreet choice for hidden or budget‑sensitive installs. Several D2 listings also show multi-size packs, which is handy if you need two matching valves.

Yes, these are thermostatic radiator valves, so they sense the room temperature and modulate flow to keep the radiator at the set level without constant manual fiddling. That delivers better comfort and can reduce energy use compared with a fixed valve. For instance, set a lower TRV level in a spare bedroom and it will stop the radiator from overheating that space while your living room stays warm.

Pick the finish to match what you can see: chrome suits contemporary bathrooms and exposed radiators for a coordinated, high‑end look, while white blends with white radiators and less visible pipework for a minimalist effect. The listings show chrome RAS‑D2 valves at higher price points than the white RAS‑C2 items, so chrome typically costs a little more but offers a more premium aesthetic. If you want to renew every visible fitting for a cohesive look, spending a little extra on chrome can make a noticeable difference.