It can be very frustrating when your radiator stops working for no obvious reason, especially as it often happens when you need your heating the most.
In this article, we'll give you 3 easy tips you can try yourself to see if it will fix the problem. It's always worth giving these a go before calling in a professional.
1. Bleed your radiator
From time to time, air can get trapped in your radiator which will usually make it feel cool at the top and hot at the bottom. The way to solve this problem is by letting (or bleeding) the air out of the rad.
The first thing to do is switch your heating system off so that you're not bleeding the radiator with the heating still running.
The take a radiator key or flat head screwdriver and locate the bleed valve at the top of your radiator. Slacken off the bleed valve and, if there's air in the system, you'll hear the hiss of air escaping. Have a cloth or towel ready to catch any escaping water.
Tighten up the bleed valve, switch on your heating system and see if it's solved the problem.
2. Check your thermostatic radiator valve
If your radiator won't get hot and you have a thermostatic radiator valve (TRV) on that radiator, then it's worth looking to see if there's a problem.
Most TRVs contain a little pin that reacts to the temperature of the room and pops in and out to allow water to flow as necessary. If the pin gets stuck then it might not be allowing any hot water into the radiator, which is why it's not getting hot.
Take a pair of pliers and open up the lockshield (non-thermostatic) valve a half turn. Then go to the thermostatic valve and open it up to full, which is often to the number 5. Leave for a few minutes and see if your radiator starts heating up.
If not, then unscrew the thermostatic radiator valve head to reveal the pin. If you press the pin and it doesn't move up or down, then it's very likely stuck.
Take your grips and gently try and move the pin up and down in order to free it off. You should then be able to press on the pin and feel it move up and down. Replace the head of the thermostatic valve and see if the radiator starts to heat up.
3. Balance your heating system
If you've got a radiator that is heating up slightly but not getting hot, it could be that your heating system is not balanced.
An unbalanced heating system is when the flow of water from the boiler and pump is not distributed evenly around all your radiators and pipes.
This usually means that hot water flows through some radiators and back to the boiler without flowing into some of the other radiators on the network, leaving them cold or lukewarm.
To balance your system, go to the radiator nearest the boiler and shut (turn clockwise) the lockshield valve all the way down. Then open the lockshield valve by half a turn and that radiator should be balanced. It means it won't be stealing all of the hot water and stopping it from flowing to the next radiator.
Repeat this process along all the radiators in your system and see if all radiators now get hot evenly.
Still not working? Call a professional
The above tips are among the most common reasons that radiators stop getting hot. They're also the easiest things to have a go at yourself without risking major damage to your central heating system.
However, if you've tried these things and none of them have solved the problem, it's best to call in a professional plumber or heating engineer and get them to diagnose the problem.
There could be issues such as sludge in your radiator, a blockage in a pipe or something more serious like a faulty heat pump or problem with your boiler. Anything relating to your boiler should be looked at by a Gas Safe Registered heating engineer and not tackled by you.
Hopefully a professional can come and see you quickly and get your heating system back up and running as soon as possible.