If your boiler is leaking, there are some checks that you can do yourself. However, you should never attempt to repair your boiler yourself – only a Gas Safe-registered engineer should conduct repairs.
There are 3 main reasons why your boiler might be leaking: there’s a pressure valve fault, a temperature valve leak or corrosion in the system. An engineer will be able to spot the problem quickly, but in the meantime there are a few things you can do:
Check the pipe fittings
If your boiler is leaking water around the pipe fittings, it could be an installation fault and you should get in touch with the engineer that fitted it. You can check the pipe fittings by drying the area then waiting to see if the water appears again. If it does, you may be able to do a ¼ turn of the pipe to stop it. However, you should still call the engineer that installed it to ask them to check the PTFE tape on the inside.
Inspect the seals
Over time, the rubber seals on a boiler can start to perish, so if you have an old boiler this could be the source of your leak. If you have a new boiler, it could be caused by your boiler running over pressure.
Heat exchanger corrosion
Unfortunately, if a boiler engineer discovers that the boiler is leaking water from the heat exchanger, this is the end of the road for your system. The heat exchanger is the most expensive part of your boiler, so it makes more financial sense to replace your boiler with a newer, more efficient model rather than try to replace it.