GETTA Help

Radiator not heating up: what to check

First establish whether one radiator, one part of the home or the whole heating system is affected. That distinction, alongside control settings and safe visual checks, gives an engineer much more useful information.

Check the pattern

  • See whether other radiators and the hot water work normally.
  • Check the timer and thermostat are calling for heat.
  • Note whether the radiator is cold throughout, cold only at the top or cold at the bottom.
  • Check for a displayed boiler fault code without opening the appliance.

Safe observations

If the radiator has ordinary accessible controls, check they have not been turned down or knocked closed. Look at the boiler pressure display only if it is visible and record the reading. Do not force stuck valves or dismantle controls.

What may be happening

Air can contribute to a cold top, while restricted circulation or deposits can contribute to cooler lower sections. A valve, system balance, pump, pressure or boiler problem may also be involved. The temperature pattern alone is not a diagnosis.

When to arrange help

Seek heating help when several radiators are affected, controls do not explain the problem, pressure repeatedly falls, a valve is stuck or leaking, or the symptom returns. Work inside a gas boiler must be left to a suitably qualified Gas Safe registered engineer.