Why is my radiator cold at the top?

A radiator cold at the top but warm at the bottom has trapped air — bleed it with a radiator key to release the air and it will heat evenly.

In more detail

If bleeding doesn't fix it, check your system pressure and that the valves are fully open.

2026 figures · BTU uses standard UK heat-loss methodology; running costs use the Ofgem price cap · always confirm with a professional.

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