Bleeding a radiator – step by step without any mistakes

If a radiator stays cold at the top and makes gurgling noises, there is air trapped in the system – bleeding it will fix the problem immediately. First turn the heating on and wait until the system is warm, then switch it off. Hold a cloth and a small container next to the bleed valve (at the top on the side of the radiator). Turn the valve slowly counter-clockwise with a bleed key or a flat-head screwdriver – air will hiss out. As soon as only water drips out (no more hissing), close the valve firmly. Afterwards, check the system pressure at the boiler: if it has dropped below 1.0 bar, top up the water until it reaches 1.2 bar. Repeat this process on additional radiators if necessary, always working from the lowest floor upwards.