If a gas boiler is leaking, you should not attempt to repair it yourself; gas boiler repairs should only ever be conducted by Gas Safe Registered engineers.
A leaking boiler is actually quite a serious problem, and indicates that an internal component such as a seal or valve is broken. The leak can lead to corrosion and rust, or can cause electric components within the boiler to short circuit. It could even cause problems throughout your house, including structural damage. As such, leaking boiler repairs should be conducted as quickly as possible.
Determining the cause of a boiler leak can be a challenge and requires finding out exactly where the leak is originating. For example, is your boiler leaking water from the bottom or is the boiler leaking water from the inside?
so.... Why is my boiler leaking?
If the boiler is leaking from the pressure valve, the pressure in the boiler may be too high. A boiler’s pressure should be between 18 and 21 PSI, or one bar, and when the pressure exceeds this value, the pressure relief valve should leak water to prevent the appliance from blowing up or rupturing. Limescale and other obstructions can cause the pressure to increase beyond safe limits. After this debris has been removed from the boiler, the valves will need to be resealed.
If the boiler leak is coming from the temperature valve, the temperature of the boiler may be too high. This may be because of a fault with the temperature probe in the boiler.
Corrosion is the main cause of many boiler leaks; corroded pipes and tanks will weaken and allow water to escape. If the corrosion is isolated to a single component, such as a valve, then you will need to have this valve replaced. However, if the corrosion is more wide-spread, your boiler may have to be scrapped as it will be beyond economical repair.
If the gas boiler is leaking water around the pipe fittings, then it may have been installed badly.
If the leak is coming from the seals of the boiler pump, then you may have to replace or reseal the pump.
Get An Engineer
While these faults are to blame for the majority of boiler leaks, the factors at play in your leaking boiler could be completely different.
Don’t attempt to touch any part of your boiler or central heating system if you’re unsure. Did you know? It’s illegal for anyone to use a gas appliance if they think it’s unsafe. It’s always better to be safe than sorry as you could make things worse.