If your boiler is running but your radiators aren't getting warm, there are several possible causes. Some are simple fixes; others point to a more serious boiler fault. This guide helps you understand what might be wrong and when a boiler replacement is worth considering.
The most likely causes are a faulty pump, a stuck or broken motorised zone valve, sludge buildup in the system, low boiler pressure, or a failed programmer or thermostat. A power flush can resolve sludge issues; other faults require a Gas Safe engineer to diagnose and repair.
If the boiler is over 12 years old and the fault is a pump or internal component failure, replacement may be more economical than repair. Recurring heating problems are often a sign that a boiler is reaching the end of its reliable service life.
From your first message to a working boiler — here's what to expect.
Answer a few short questions. Takes about two minutes. You can add photos of your boiler or any error codes showing.
We connect you with a Gas Safe registered installer in your area who can visit quickly and assess the job.
Your installer gives you a clear written price before anything starts. No surprises and no obligation to proceed.
Answers to the questions we hear most often.
Answer a few questions and we'll connect you with a Gas Safe installer in your area.
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