Help! My Boiler is Leaking Water – What Should I Do?

Help! My Boiler is Leaking Water – What Should I Do?

Posted on April 27, 2021

Whilst you can’t fix this yourself, there are a few things you can do to limit the damage caused by a leaking boiler. So, first things first – If your boiler is leaking:

  • Switch off the water supply to stop the leak
  • Turn off your heating so that water stops circulating around your heating system
  • Clean up any water from the leak
  • Call a Gas Safe registered engineer to come and take a look

It’s really important to call a Gas Safe engineer and not try to fix the problem yourself. At the first sign of a leak from your boiler – even just a small one – call in the experts. Aura Heating heating engineers are trained to identify and repair these faults and can get them fixed for you quickly and accurately.

Even a small leak can lead to corrosion, rust or the malfunction of electrical parts, so don’t delay! After all, even a small leak from your boiler isn’t going to get better by itself.

So now we’ve covered what to do if you boiler is leaking water, let’s talk about what could be causing the leak. 

Why is my boiler leaking water?

The most common causes of a leaking boiler are corroded pipes, high pressure, loose pipes or poor installation (particularly if it’s a new boiler). There are 7 common causes of a boiler leaking water that we’re going to take a look at here.


Corrosion in parts of your boiler like the pipes or tanks could cause them to start to weaken over time. This corrosion weakness could then result in water escaping from them, thus causing a leak from your boiler. If you catch it in time, perhaps when it’s just a small leak, you may find that you can just replace a single pipe or valve where the corrosion has started, rather than allowing it to spread and require a larger, more costly repair later. If corrosion is left to spread throughout the whole system, you’re more likely to need a replacement boiler.


A leaking boiler could be down to the pressure being too high. You can check your boiler pressure by looking at the pressure gauge. It should be between 1 and 2 (always consult your user manual for your specific unit). If the gauge is reading over 2, the boiler pressure is too high. To avoid imploding, the boiler will need to let out some of the excess pressure and this can cause a leak.


The TCV in a boiler is the temperature control valve which keeps track of the water temperature within the boiler to make sure it doesn’t get too hot. If there is a leak from the temperature valve, it is likely that the water inside the boiler is too hot. Be careful – This can result in scalding hot water coming out of your taps.

Pump Seals

Your heating system works by the pump pumping water around your home. If the pump isn’t sealed properly, water can leak out. If the pump is the source of your boiler leak, it will need to either be replaced or resealed.

Loose Joints

Over time, joints and pipe connections will loosen slightly through natural wear and tear. The temperature changes in the pipes cause lots of expanding and contracting as it heats and cools, which will eventually affect the pipe joints and connections. If this is the cause of your boiler leak, you will need to tighten up the joints and connections which will stop water leaking out.

Poor Installation

If your boiler is new and starts to leak water, it could be that it has been installed poorly or incorrectly. This is likely the case if you find water leaking from the pipe fittings. You should be able to prevent this happening by always using a Gas Safe registered engineer to complete any boiler repairs or replacements.

My boiler is leaking water – What do I need to know?

When it comes to boiler issues like a leak, there are a few commonly asked questions.

Is a leaking boiler an emergency?

Not in the sense that a gas leak is an emergency, but it is a serious fault that needs urgent attention from a professional heating engineer. Not only could it result in further damage to your boiler itself, it could also end up damaging your home.

If my boiler is leaking, can I still use it?

You shouldn’t continue to use a leaking boiler. Switch off the water supply, turn off the heating and call a heating engineer.

My boiler has low pressure – Is it a leak?

Having low boiler pressure often means there is a leak somewhere in your heating system. It won’t be working efficiently in this state, so call in the experts.

Is a leaking boiler dangerous?

Perhaps not in the same way as a gas leak, but it does have the potential to cause a lot of damage – And not just to your boiler, but your home as well. If your boiler is leaking water, then there’s a good possibility that water is going onto electrical components which could results in short circuiting. It depends on where your boiler is located, but if it’s leaking onto carpets or furniture that water is going to cause potentially extensive damage.

Can I prevent my boiler from leaking?

After reading all of this, you’re probably hoping there’s a way to stop your boiler leaking in the first place. And there is! This is where those all-important annual boiler services come in. We don’t recommend a yearly boiler service for nothing! Carrying out this essential regular maintenance helps to make sure your boiler stays in good working condition as well as catching any problems before they cause bigger issues or boiler breakdowns. Keep your boiler running reliably, safely and efficiently with an annual boiler service. If you are an Aura Heating Care Plan customer, your yearly boiler service is included in the price. Head to our website for more information or to book yours in.

You could also consider having a chemical flush of your heating system to get rid of debris and limescale. You can also fit a magnetic filter to remove debris before it builds up and causes problems.

Time for a new boiler?

If your boiler is over 10 years old and leaking, it’s maybe time to think about getting a new one. They don’t last forever, and natural wear and tear over time will gradually make it less reliable and efficient.

Replacing an old, leaking boiler won’t just mean you stop that pesky leak, it will also be more efficient and could save you money on your energy bills too. It’s also better for the environment to have an efficient boiler!

If you think it’s time for a new boiler, head to our website where you can get a quick estimate.

Get in touch

If you have a leaking boiler, give us a call here at Aura Heating. Our expert heating engineers will be pleased to identify the issue and get it solved for you as quickly as possible.