Updated on 23rd August, 2023 by Martin Astley
If your radiator is not heating up properly, identifying the source of the problem can be a challenge, but with a little time and a lot of patience, you may be able to get your central heating back on without making a claim on your cover.
Are all the radiators cold?
If all the radiators are cold or if your radiator is not getting hot, check that your boiler and central heating are switched on. It might sound obvious, but sometimes the obvious answers are the right ones! If everything is switched on, then the problem is likely to be with your boiler, plumbing, or pipework, and it is highly inadvisable (and may even be illegal) for you to attempt to fix the problem. You will need to call out the professionals and arrange a boiler repair.
Is only one radiator cold?
If just one radiator is cold, the problem is almost certainly isolated to the broken radiator, and you may be able to repair it yourself.
Part of the radiator is warm
If part of the radiator is warm, then it is likely that you are experiencing one of two common problems. If the radiator is cold at the top, you will need to bleed the radiator to expel any air from the system. The bottom of the radiator will be full of hot water, but this heat will be unable to reach the top because of the air bubble. Check out our instructions on how to bleed a radiator for more information. Bleeding a radiator is a very easy task and will only take you a few seconds if you have the necessary tools at hand.
The top half of the radiator is warm, but the bottom half is cold
If this is the issue, you will have a larger job on your hands. There will be a thick layer of sludge at the bottom of the radiator, which will stop it from heating up properly. You will have to remove the radiator from the wall and the plumbing and rinse them through. Don’t forget that water will gush out of the radiator when you remove it, so be prepared with pans and towels. See our advice on how to clean a radiator for step-by-step guidance.
The entire radiator is cold
check that the thermostatic radiator valve and the second valve on the other side are open and that the pins within the thermostatic valve are moving properly (you will have to remove the top of the valve). You can check if a thermostatic valve is working properly by taking the head off and seeing if the pin moves down and up freely. If it is stuck, give it a careful tap to free it up.
What if this does not work?
turn off all the radiators in the rest of the house to see whether or not the broken radiator heats up. If the radiator warms up, then turn your other radiators on one-by-one. You can then identify any other radiator problems and find out which other radiators may need bleeding. If your cold radiator still won’t heat up, you might need to replace the valve.
Still no luck?
Not all radiator breakdowns can be resolved without the help of a professional, and if the advice you’ve received has not resolved your problem, you’ll need to get someone out as soon as possible.
Don’t attempt to touch any part of your boiler or central heating system if you’re unsure or not confident. Did you know that it’s illegal for anyone to use a gas appliance if they think it’s unsafe? It’s always better to be safe than sorry, as you could end up making things worse.
Instead, be sure to call us at (0345) 3192-247 for more information, and please be sure to take a look at our central heating cover plans. These cover plans are designed to give you peace of mind for when your radiators are not working, you encounter boiler problems, or if you have issues with your central heating system.
247 Home Rescue accepts no liability for any injuries or damages you sustain following the advice on this website. If in doubt, seek professional assistance.