Bathroom radiators work the same way as any other radiator, but they’re taller and extend further upwards. While radiators are reliable and rarely need maintenance, they may start working poorly after a while and won't heat up.
There are a few things you might notice:
- The radiator is cold at the top, or has cold spots
- The radiator is colder than it should be/compared to others
- The radiator rattles or thumps more than it has done before
In any of these scenarios, consider bleeding your radiators.
How to bleed the bathroom radiator
Bleeding radiators releases excess air preventing water flow around the radiator.
This is generally one of the first troubleshooting steps to take if you notice poor radiator performance, especially if it’s just one or two radiators that appear dysfunctional or whether some of the radiators heats up while the rest remains cool.
To bleed the bathroom radiator, you’ll need four things:
- A bucket or cup
- A cloth to collect any leaking water
- A radiator bleed key
- You can also use a flathead screwdriver
- Gloves to protect your hands from any hot water
Firstly, let the heating system cool completely. Turn off the heating and leave the radiators for half an hour, ensuring they’re totally cold. If you don’t do this, any escaping water might burn you.
Next, check the lockshield valves - these are often covered with plastic caps. The lockshield valves should be turned fully open. This may be the case already. You can bleed the radiator without doing this, but it’ll be more efficient if you open them.
Then, follow these steps:
- Put on the gloves and place the cloth under the bleed valve. Gradually insert the key into the valve and start turning it.
- If the radiators have been painted, the valve might be clogged with paint. In this case, you’ll need to de-clog the valve by digging out the paint. You also might need to partially dismantle the valve.
- The best scenario is that most air and some water will bleed, or hiss out of the valve, which you can collect with the cloth.
- Wait until the hissing stops, and close the valve. If excess water comes out, collect it in the mug. Don’t worry if it’s not a lot.
- Close the valve once all air has leaked out.
- You might need to open and close the valve a few times over the course of a few minutes to ensure all air escapes.
- Once finished, repeat for all other radiators.
- If too much water leaks out, you may need to check your boiler pressure (normal pressure is typically between 1 and 2 bar, but this depends on the boiler).
Make sure you close the valve once the air stops. You’re supposed to be releasing air - not water. Open the valve gradually to avoid too much water coming out.
How does air get trapped in the radiator?
Air can get trapped in the radiator when the system is not fully bled, and air bubbles are stuck in the system.
This can happen when the system is not properly vented, e.g. there’s an issue with the cold water feed. Additionally, if the radiator valves are loose or not properly sealed, air can leak in and become trapped in the system.
Another possibility is there are pinhole leaks in pipes. In essence, any fault or issue which exposes the heating system to air can cause trapped air. In most cases, air can be released via bleeding, but other times, it might cause a total air block wpreventing radiators from working
Why bleed a radiator?
Bleeding a radiator is a necessary maintenance task that should be undertaken on a regular basis to ensure your radiator is working properly. It’s a pretty simple process which involves releasing any air that has accumulated in the radiator.
Radiators come with ‘bleed valves’ designed for this specific task. This is typically a small brass valve located near the top of the radiator. You can open the valve with a flat screwdriver, but you’re better off using a specifically designed bleed key.
Always open bleed valves gradually - and always shut your heating off beforehand to enable the water to cool!
When to bleed a bathroom radiator?
If your radiator seems to heat up slowly or only heat up at the bottom, then it might need bleeding.
Bathroom radiators and heated bathroom towel rails are usually pretty tall, which makes it conspicuous if they’re only heating up at the bottom and not the top. Since you probably drape towels over the top to dry, this is an annoying issue.
Bleeding a bathroom radiator is a relatively simple procedure that should be done every few months to ensure that your radiator is operating correctly and efficiently. When a radiator is “blocked,” it has air trapped inside, preventing it from heating up efficiently.
Bleeding a radiator is the process of releasing the trapped air so that the radiator can warm up correctly, and is relatively easy to do on your own without minimal tools or experience.
So, in short, if your bathroom radiator or heated towel rail isn’t heating up properly, then consider bleeding it. This is especially true if other radiators seem to be working fine or if only the bottom and not the top of the radiator is heating up effectively. For year round cover take a look at our plumbing cover, for your peace of mind.
