How to bleed your radiators
Over time, air can become trapped inside your radiators. This means that the radiator doesn’t heat you or the room as well as it should. If you think that a room in your house is colder than it used to be, there’s a good chance that the radiator needs bleeding. It’s a good idea to bleed your radiators a couple of times a year.
Getting back some warmth
The first thing you will need to do is make sure you have the right tools for the job, namely a radiator key and an old towel or cloth. If you don’t have a radiator key it is possible to use a pair of pliers carefully, but we wouldn’t recommend it. Radiator keys are cheap and widely available in hardware stores and online.
You can check each radiator to see which ones need bleeding, but we generally just bleed them all for good measure and it’s safer to do so when the central heating is off and the radiators are cool. The radiator that is most likely to need bleeding is the highest one in the house, in most cases, this is the towel rail in the upstairs bathroom.
At the top of each radiator will be a square bolt, usually on the right-hand side, this is where you attach the radiator key and carefully release the screw thread. It’s best at this point to cover your hand and the key with the old towel or cloth to avoid the water from the system squirting out. Unscrew the bolt slowly and carefully as often the water in the central heating system will be pretty dirty so you want to make sure you can soak it up as it comes out.
If the radiator is full of air you will hear a hissing sound as the air is released until eventually water starts dribbling out, this is when the radiator has been fully bled and you can tighten up the screw again.
One last step
If there has been a lot of air in your radiators you may find that you need to recharge the pressure in your central heating system. You do this at your boiler by opening the pressurizing tap on the filling loop, the filling loop is usually directly under the pressure gauge. If you can’t find it then it may be best to look at your boiler manual or search on Google for your boiler manual if you can’t find it... this bit is a bit tricky but not impossible to do yourself. If you're in any doubt track down a friendly plumber.
If you haven’t bled your radiators for a while you should notice a significant improvement in how warm your house feels and if that’s not enough why not check out the SpeedComfort!