How To Bleed Your Radiators

Bleeding your radiators needs to be done when air has been trapped inside them causing there to be cold spots, therefore reducing the overall efficiency of the radiator. When you bleed a radiator, you are essentially just letting that trapped air out so that you can improve the efficiency of the entire heating system. It is quite easy to bleed your radiators yourself, just follow these simple steps:

Find the problem

Start by turning the radiators on and letting them heat up fully. Wait until the radiators are fully heated so that the pressure in the radiator can build up in order to force the air out. You will then need to check each radiator in the house to make sure they are all working properly. If a radiator takes a long time to heat or you find any cool spots, particularly near the top of the radiator, this indicates that the radiator needs bleeding.

Turn off the heating

Now you need to turn off the heating again before actually bleeding the radiator and let it cool to ensure you don’t injure yourself or get water all over the floor.

Bleeding the radiator

You will need a radiator key (depending on your radiator) and some cloths. Look for a valve at the top of the radiator on one of the ends. Insert your radiator key into this valve, holding it with your cloths to catch any drips. Slowly turn the radiator key anti-clockwise and listen for a hissing sound – this sound is the trapped air escaping.

Radiator Keys

Closing the valve

It is important to listen to the sound of the hissing to identify when you need to close the valve again. The hissing will start to get fainter as water travels up the radiator and will eventually start to spill out, so be ready to close the valve quickly. Repeat this process on all radiators that need it.

Checking the pressure

Finally, you will need to check the gauge on your boiler to ensure the pressure is at the right level. If the pressure is too low then you will need to top it up. You might want to check your boilers instructions to do this, but you will probably need to top the pressure up using the filling loop.