Learning how to bleed a radiator is simple and with the right steps, anyone can complete this job, getting the radiator functioning at the maximum level.
Is there a problem with the radiator in a room of your home? You might find that it is not heating up properly. Or, perhaps it’s just taking a while to heat up.
This is usually due to the fact that air bubbles are trapped in the heating system. Pockets of air will stop the hot water in your radiators from moving around all areas of the radiator.
Recommended reading: No Hot Water from Boiler: Our Ultimate Troubleshooting Guide
As such, they won’t be able to heat up as much as they should, or the water can take a while to get around the hot air.
Bleeding the radiator is the solution you are searching for.
By bleeding a radiator, you can remove the air and make sure that your radiator is heating your home at an efficient and effective level.
You might think that bleeding a radiator is a complicated job and you may even consider calling in a central heating engineer.
But there’s good news on that front because learning how to bleed a radiator is simple and with the right steps, anyone can complete this job, getting the radiator functioning at the maximum level.
Here are the steps that you need to follow, but before that…
Which Radiators Do You Bleed First?
If your house has 2 floors you should begin bleeding the downstairs radiators first. It’s also advisable to start with the radiator which is furthest away from the boiler.
Once you’ve bled all the downstairs radiators you move on to the upstairs, again beginning with the radiator which is furthest from the boiler.
How to Bleed Radiators
1. Check The Top And Bottom Of The Radiator
You do need to make sure that you check all areas of the radiator. Switch the radiator on and wait for it to heat up.
Lightly, touch the top and bottom of the radiator. Is the top cold and the bottom warm? If that’s the case, your radiator does need bleeding.
The trapped air bubbles typically rise, blocking the water from reaching the top of the system. Removing them will have your radiator working as good as new once more.
2. Get The Tools You Need – Radiator Key
There are a few items you’re going to need to bleed a radiator, most of which you’ll have lying around your home.
You need, a cloth, a radiator key, protective glasses and gloves and a small container of some sort to catch excess water.
If you don’t have any of these items, you can probably find them at a DIY shop.
3. Turn Off The Heating
It is important that you do turn off the heating before you start bleeding your radiator.
Water often does leak out during the process, and you don’t want it to be hot. That could lead to a nasty burn.
If your radiator was on, leave it a couple of hours before attempting to bleed it.
4. Locate The Radiator’s Valve
Look for the shank on the side of the radiator. This is a metal nob which your radiator key will fit perfectly onto.
Once you have found this, you can put your small container directly underneath it to catch the excess water.
This will only be a few drips, but it will save you cleaning it up off the floor later.
5. Use The Radiator Key
Once you have put on your gloves and glasses, you can hold the cloth underneath the radiator valve incase water does drip out. Congratulations, you’ve reached the stage where you can now bleed the radiator.
Use the key to turn it slowly anti-clockwise towards you. You only need to turn it about a quarter of the way before you hear a hissing sound. This tells you that the air is escaping.
You should make sure that the radiator key stays on the valve until the hissing stops. When it does, you can immediately turn the valve clockwise.
Usually, this is the point when the water will drip out so if you are quick enough to notice there will only be a few droplets and your cloth will stay relatively dry.
6. Close The Radiator’s Valve
Closing the valve will stop both the hissing and the water. You can then wipe off any water that has dripped down the radiator or over the valve.
Make sure you do close the valve tightly, or you could find you come back later to a small puddle on the floor. If the valve isn’t closed, water will slowly trickle out.
7. Repeat the Process on All Radiators
To ensure all excess air has been drained from your heating system, it’s best to bleed all of your radiators, even if you’ve only been having problems with one.
For a well-maintained heating system, you should try bleeding your radiators regularly. An annual bleeding plus a bleeding after any repairs or modifications to your heating system is usually plenty.
8. Turn Your Heating Back On
Now that the trapped air is gone, you can turn your heating back on. You should see that radiators heat up normally and a lot quicker than they were previously.
If any of the radiators isn’t, there could be a different problem inside the radiator. If there are cold spots, you might have a blockage of grime in the pipes.
Grime can be pushed through the heating system, eventually, ending up in your radiator, blocking parts of it off.
If that happens, it’s best to call in a pro because this is quite difficult to fix – a power flush may be needed.
9. Check your Boiler’s Pressure
Check the boiler’s pressure by having a look at the gauge on your boiler. If the pressure is too low, you’ll need to “top up”. You can do this using the lever or tap on your boiler, known as the filling loop.
Recommended reading: Boiler Filling Loop: Installation, Repair & Replacement
Afterwards, you may want to run another test to check that your efforts have been successful. Simply turn your heating on, wait for all the radiators to heat up and check for any cool spots.