How to bleed a radiator

How to bleed a radiator step by step – a practical guide for tenants. If the radiator in your apartment is cold at the top and warm at the bottom, or you hear gurgling sounds, there is most likely air trapped inside. In this guide, we explain how to bleed a radiator yourself at home and when to report the issue to the property manager.

How to tell if your radiator needs bleeding?

The most common signs of air in a radiator are:

• radiator warm at the bottom, cold at the top,
• uneven heating of the room,
• loud gurgling or hissing inside the radiator,
• knocking sounds after turning the heating on,
• no response when adjusting the thermostatic valve.

What do you need to bleed a radiator?

Before you start, prepare:

• a radiator bleed key (or a flat screwdriver if the valve has the right slot),
• a small bowl or cup,
• a cloth to wipe up any water,
• old towels to protect the floor.

How to bleed a radiator step by step

1. Turn on the heating and warm up the system

Set all radiators to maximum and let the system run for 10-15 minutes so that any air gathers in the upper parts of the radiators.

2. Turn off the heat source (or central heating pump)

In single-family houses, turn off the central heating pump. In apartment blocks this step is not needed.

3. Find the bleed valve

It is usually located at the top of the radiator, on the opposite side of the thermostatic valve. It looks like a small square or hexagonal screw.

4. Place a bowl under the valve and slowly open it

Use the bleed key or screwdriver to turn the valve a quarter or half turn counter-clockwise. You will hear a hiss – that is the air escaping.

5. Wait until water comes out

When a steady stream of water (without bubbles) comes out of the valve, the air has been removed. Tighten the valve carefully – do not use force, so you do not damage the thread.

6. Check the system pressure

In single-family homes check the boiler pressure on the gauge. If it has dropped below 1 bar, top up the system with water according to the boiler instructions. In apartment blocks the building manager takes care of this.

When to call the property manager?

Contact the property manager or Golden Square if:

• the radiator does not heat up at all even after bleeding,
• water leaks from the bleed valve,
• the system pressure keeps dropping,
• you hear loud knocking in the pipes,
• you cannot locate or open the bleed valve.

Bleeding a radiator is a simple maintenance task that every tenant can do at home. If you have any doubts, our team at Golden Square is happy to help.