How to fix radiators that aren’t warm enough & aren’t getting hot

Whilst your boiler and radiators might be in good working order, you may find that your heating isn’t working up to standard from time to time.

Thankfully, there are ways of checking that everything is working correctly. However, it is strongly advised that you don’t attempt to conduct any engineering on the radiators as this could be dangerous. You can find your nearest heating engineer with HomeServe – our experts are all Gas Safe-registered, so we know radiators and central heating systems inside out.

Read on to discover more about the small checks you could make at home to help diagnose the problem:


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Steps to improve your radiator


  • Check that the radiator valve is open

The most common type of radiator valve is the angled variety. They include thermostatic, manual and lockshield valves and typically join a horizontal pipe with a vertical one.

Many modern radiators have valves with temperature gauges that go up to five or six and can be controlled by a simple turn to allow water in our out. Check that your valves are open by turning the knobs that are located at the bottom left of your radiators anticlockwise and back again.


  • Ensure that the radiator thermostat valve is set correctly


Thermostatic radiator valves (TRVs) tend to be self-regulating and are manufactured to control the temperature of a room through the movement of a pin inside the valve head according to the expansion or contraction of a liquid or wax. If they are set too low, the radiator will not receive sufficient water to heat the room, so you could check that they align with your thermostat first.

Technology has introduced electronic TRVs that allow you to control the central heating from your phone, so, whilst it might be more expensive, it may be easier to monitor and identify any potential problems quickly.


  • Check that the lockshield valve is set correctly


Located at the opposite end of the radiator to the main valve, the lockshield valve controls the flow of hot water into the radiator. In order to allow more hot water to pass through, the settings may need to be changed.

It’s possible to adjust thermostatic valves by hand, but a valve adjuster or spanner is required to tweak the lockshield – this is why it is best left to a professional engineer. Contact us if you’re in need of assistance, our friendly engineers have the skills and experience to fix this issue.


  • Check whether the valves are blocked

Limescale can sometimes build up inside the radiators, which means the system may need to be flushed out. Our Gas Safe registered engineers are all trained to conduct a professional system Powerflush – a measure that involves sending a chemically-infused liquid at a high velocity through your system to rid it of any inhibiting substances and restore your central heating’s efficiency.

It is crucial to remember that you should only perform checks on your boiler that are simple with minimum risk. Do not attempt to fix the issue yourself as this could be extremely dangerous.

All of our engineers are Gas Safe-registered and fully qualified to diagnose and fix your central heating problems, so whether you know what the problem is or not, you can book an appointment with a local expert to diagnose the issue and get your heating back up and running effectively again.

Information and other materials on this website are not intended to constitute professional advice and should not be relied upon. Please see our Terms of Use for further details

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