Bleeding a Radiator
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What Does “Bleeding a Radiator” Mean?
Bleeding a radiator means releasing trapped air from inside it. Air can collect at the top of a radiator, stopping hot water from circulating properly.
Why Would You Do It?
You might need to bleed a radiator if:
- The top of the radiator feels cold but the bottom is warm.
- You hear gurgling or bubbling noises inside the radiator.
- Your heating system isn’t warming up as efficiently as before.
How to Bleed a Radiator
- Find the Bleed Valve
- It’s usually at the top corner of the radiator. You’ll need a radiator key (or sometimes a flat screwdriver).
- Place a Cloth or Container Under the Valve
- To catch any drips.
- Open the Valve Slowly
- Turn the key anti-clockwise just a quarter-turn.
- You’ll hear a hissing sound as the air escapes.
- Close the Valve When Water Appears
- As soon as water (not air) comes out, tighten the valve back up.
- Check the Heating System Pressure
- Bleeding may lower the pressure in your system. If it’s too low, you may need to top it up, please see ‘Topping up System Pressure’
When to Call Us
- If you need to bleed radiators very often (could be a bigger issue).
- If water keeps coming out dirty or discoloured. If system filled with antifreeze, the water may be discoloured yellow/red colour
- If your boiler pressure drops quickly after bleeding.
Video Link: Bleeding a Radiator
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At a glance
What Does “Bleeding a Radiator” Mean?
Bleeding a radiator means releasing trapped air from inside it. Air can collect at the top of a radiator, stopping hot water from circulating properly.
Why Would You Do It?
You might need to bleed a radiator if:
- The top of the radiator feels cold but the bottom is warm.
- You hear gurgling or bubbling noises inside the radiator.
- Your heating system isn’t warming up as efficiently as before.
How to Bleed a Radiator
- Find the Bleed Valve
- It’s usually at the top corner of the radiator. You’ll need a radiator key (or sometimes a flat screwdriver).
- Place a Cloth or Container Under the Valve
- To catch any drips.
- Open the Valve Slowly
- Turn the key anti-clockwise just a quarter-turn.
- You’ll hear a hissing sound as the air escapes.
- Close the Valve When Water Appears
- As soon as water (not air) comes out, tighten the valve back up.
- Check the Heating System Pressure
- Bleeding may lower the pressure in your system. If it’s too low, you may need to top it up, please see ‘Topping up System Pressure’
When to Call Us
- If you need to bleed radiators very often (could be a bigger issue).
- If water keeps coming out dirty or discoloured. If system filled with antifreeze, the water may be discoloured yellow/red colour
- If your boiler pressure drops quickly after bleeding.