Quick answer
A leaking radiator valve can lower heating-system pressure and damage floors. If safe, catch drips and turn off the heating, but do not force the valve or dismantle it.
Identify and contain the leak safely
Water may appear around the valve body, pipe connection or spindle. Heating water can be hot, so let the radiator cool before approaching. Place a container or towel beneath a small drip if safe, and protect nearby belongings.
If water is near electrical fittings or appliances, keep clear. Turn off electricity at the consumer unit only if you can reach it from a dry, safe place. Do not touch wet electrical equipment.
What you can check
- 1Turn the heating off using its normal controls and allow the radiator to cool.
- 2Observe whether the leak continues when cool; note whether water appears at the valve, joint or pipe.
- 3If a separate radiator isolation control is clearly identified and operates normally, follow its instructions only if you are confident. Do not force a stuck valve or remove any part.
- 4Check the boiler pressure display and manual, and note changes without repeatedly topping up the system.
Arrange a proper repair
A valve may need a seal, connection or valve replacement, and the system may need draining or other specialist work. Do not use putty or sealant as a permanent fix, and do not loosen a nut while the system is pressurised.
A plumbing or heating professional can identify the leak and check whether pressure loss has affected the system. Any work involving gas or the inside of a boiler must be done by a Gas Safe registered engineer. TraceFix handles plumbing leak investigation in Birmingham and London.
When to call a plumber
- Water is escaping steadily or cannot be contained.
- The leak is near electrics or damaging floors and ceilings.
- The radiator valve is stuck, hot or difficult to identify.
- Boiler pressure keeps falling after the visible leak is addressed.