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Heating

Why are my radiators cold at the bottom?

5 min readGas Safe registered advice · West Midlands 

Radiator cold at the bottom in Stourbridge, clean white central heating radiator on a plain wall

Where the cold patch sits on a radiator tells you most of what you need to know about what's gone wrong.

Cold underneath: sludge

Magnetite, a black iron oxide sludge, collects at the bottom of radiators as the system corrodes over the years, and it slows or stops the flow of hot water through the panel. Older properties across the West Midlands with original steel pipework tend to suffer from it more.

Cold across the top: air

Air rises, so a radiator that's cold across the top but warm lower down just needs bleeding. That's a job you can sort yourself in a few minutes with a radiator key.

Dealing with sludge

Treatment depends on how far the build-up has gone:

  • A chemical cleanse and inhibitor dose for milder contamination.
  • A full power flush where sludge has spread through several radiators.
  • Removing and flushing individual radiators where only one or two are affected.

Keeping it from coming back

A magnetic filter fitted to the system, along with the correct dose of inhibitor, keeps a cleaned system clean, and both are checked as part of an annual service. If you'd rather hand it to someone qualified, we work right across Halesowen, Stourbridge, Dudley and the wider West Midlands, and we book urgent repairs in fast, usually next day.

Want it done for you?

If you want your plumbing or heating problem fixed professionally for you, contact IJS Trade Services today for fast, reliable service across the West Midlands and surrounding areas.

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