Radiator valves: thermostats, valves and sensors
Radiator valves are how the radiator “listens” to the room. Without a valve and thermostatic head you only regulate heat via the boiler/whole system — less comfortable and often costlier. This guide teaches choosing valves by connection and job.
Radiator: how to choose a radiator. Thermostat logic: what a thermostatic valve means.
What is in the kit
- Thermostatic valve — mechanism that closes/opens flow.
- Thermostatic head / sensor — the “head” that feels room temperature and drives the valve.
- Return / shut-off valve — lets you isolate the radiator for service and balance.
Often you buy a kit (valve + head). Danfoss examples: straight DN15 kit, angled kit, axial. Heads separately: Danfoss Redia, Danfoss Eco®.
Straight, angled or axial
| Type | When | Example |
|---|---|---|
| Straight | Pipes come straight to the valve | Danfoss straight DN15 |
| Angled | Pipes from wall/floor at an angle | Danfoss angled |
| Axial | Special connection geometry | Danfoss axial |
Type is set by pipe geometry, not design. Photograph the existing node.
Other examples in the range
Purmo VKO line: thermostatic valve. Heimeier: three-way — for more specific nodes, not a “default head on every panel”. Before buying, read the card: what it is for.
Compatibility head ↔ valve
“Any head on any valve” is a myth. Thread and series must match. Safest DIY path: a kit from one brand or clearly stated compatibility. More: explanation.
Typical mistakes
- Buying an angled valve when you need straight (or vice versa).
- Leaving the radiator without a head “because it is warm anyway”.
- Mixing brand heads without a compatibility check.
- Forgetting the return valve — makes service harder.
Short path
- Determine connection geometry (straight/angled/axial).
- Choose DN from the existing / radiator card.
- Take a kit or a verified head+valve pair.
- Assemble with a radiator from Radiators.
Danfoss · Heimeier · Purmo. Pillar: heating map.
Reviews
Be the first to review this article.
Write a review