Central Heating and Radiators
Cold radiators, a leak, heating that won't come on or a room that never warms up? BoilerWell repairs and improves central heating: radiators fitted, replaced and repaired, valves, controls and thermostats, and power flushing.
Or send a photo of the radiator on WhatsApp.
Gas Safe registered heating engineer. Based in Pontypridd, South Wales.
Why choose BoilerWell for your heating
- One local heating engineer. Gas Safe registered and based in Pontypridd, for radiators, controls and the boiler alike.
- The cause, not just the symptom. A cold radiator can be air, sludge, a valve or the balance of the system, and you’ll know which before anything is changed.
- Agreed before work starts. You know what’s involved, and what it affects, before any floorboards come up.
Where is your radiator cold?
Where a radiator stays cold says a lot about why. Here’s what each pattern usually means, and what’s safe to try first.
Cold at the top
What it can mean. Air trapped in the radiator. Air rises to the highest point, so the top stays cool while the bottom heats up.
What you can do. Bleeding the radiator usually lets the air out. On a sealed system, such as most combis, check the boiler pressure afterwards, because bleeding can lower it. If a radiator keeps needing bleeding, air is getting in somewhere, and that’s worth a look.
Cold at the bottom
What it can mean. Sludge: rust and debris from inside the system settle along the bottom of the radiator and stop water flowing through it.
What you can do. Bleeding won’t clear it. The system needs looking at, and if sludge is the cause, cleaning. For some systems that means a power flush.
Cold all over
What it can mean. A valve that’s closed or stuck (thermostatic valves often stick after a summer unused), a blockage, or water not reaching that radiator.
What you can do. Check that the thermostatic valve is turned up. If the radiator is still cold with the heating on, the valve may need freeing or replacing.
Some rooms never warm up
What it can mean. A radiator too small for the room, a system that isn’t balanced, so the radiators nearest the boiler take most of the heat, or controls in the wrong place.
What you can do. Note which rooms, which radiators and when. It helps narrow things down on a visit.
Based on manufacturers’ guidance: Baxi, Why are my radiators cold?; Vaillant, Power flushing, checked 11 November 2026. Every system is different, so the cause is confirmed on a visit.
Heating work BoilerWell does
- Radiators
- New and replacement radiators, the right size for the room, fitted with new valves.
- Radiator repairs
- Leaking radiators, weeping valves and joints, and radiators that won’t heat.
- Valves and controls
- Thermostatic radiator valves, room thermostats and programmers, fitted and set up.
- Power flushing
- For systems where sludge is stopping radiators heating, once the system has been checked.
- Heating pipework
- Leaks repaired, and pipes altered for a new radiator position or a new layout.
- Central heating installation
- A full system: boiler, pipework, radiators and controls planned together.
How a heating job works
- Say what's happening, or what you'd like done: online, by phone or on WhatsApp, with a photo if you can.
- A visit to look at the radiators, the pipework and the boiler, arranged with you.
- A plain explanation of what's needed, and a quote before any work starts.
- The work done, then the system refilled, bled and checked for leaks and for heat at every radiator worked on.
When central heating pipework needs attention
- A leak, a drip or a damp patch near a pipe, a radiator valve or the boiler
- Pipes that bang, knock or creak when the heating comes on
- Topping up the boiler pressure often, which can mean a leak somewhere in the system
- A radiator that needs moving for a new kitchen, a new layout or a bigger radiator
Pipes under floors or behind boxing are opened up only as far as needed, and only with your agreement. If the problem is the boiler itself, see boiler repairs.
What affects the cost
- How many radiators are involved, and their size and type
- Whether pipework needs moving, extending or replacing
- Access: floorboards, boxed-in pipes and where the pipes run
- The condition of the water in the system, and whether it needs cleaning
- The valves and controls you choose
Every quote is written for your home after the work has been looked at. There are no fixed prices on this website.
24/7 emergency call-outs
If your heating has failed, your boiler has broken down or a pipe has burst, call BoilerWell at any time, including nights, weekends and bank holidays. Say what's happening and you'll get a straight answer on what can be done and when. You won't be promised an arrival time that can't be kept.
Heating engineer in Pontypridd, Rhondda Cynon Taf and Cardiff
BoilerWell is based in Pontypridd and works on central heating and radiators across Rhondda Cynon Taf and Cardiff. Enquiries from Caerphilly county borough, Merthyr Tydfil and further afield are welcome: availability is confirmed after BoilerWell reviews the job. You deal with BoilerWell directly, from the first look to the finished work.
Related services
Central heating and radiator questions
Why isn't my radiator heating properly?
It depends where it's cold. Cold at the top usually means trapped air. Cold at the bottom often means sludge has settled inside. Cold all over can be a valve that's closed or stuck, or water not reaching that radiator. If bleeding doesn't sort it, the cause is found on a visit rather than guessed.
Can an existing radiator be replaced?
Yes. A like-for-like replacement is the simplest, because the pipes are already in the right place. A radiator of a different size or style may need the pipework adjusting, which is checked before you're quoted.
Can a radiator be moved to another wall?
Often, yes. It depends on how the pipes can reach the new position, under the floor or along the wall. That's looked at on a visit before you're quoted.
What happens during a radiator installation?
The heating is drained down, fully or in part. The old radiator comes off, new brackets go up, and the new radiator is hung and connected with its valves. The system is then refilled and bled, the joints are checked for leaks, and the radiator is checked as it heats up.
Do I need a power flush?
Not always. A power flush is for a system where sludge is restricting the flow: radiators cold at the bottom, slow to warm up, or needing bleeding often. It's only recommended once the system has been looked at.
When should I contact a heating engineer?
When a radiator is still cold after bleeding, when a radiator, valve or pipe is leaking, when you're topping up the boiler pressure often, or when parts of your home never get warm. If water is leaking and you can't stop it, call.