How to fix a Leaking Boiler

Some possible reasons why your boiler might be leaking and how to fix them

How to fix a Leaking Boiler

February 10, 2020

It is likely that you have noticed your leaking boiler at the most inopportune time, and it is causing you a lot of stress. However, depending on the reason behind your boiler leaking, you may be able to get it fixed quickly and possibly even for free.

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You will know that you have issues with your boiler when you see water dripping from the boiler, or perhaps you have noticed a puddle of water underneath the appliance.

No matter what you have noticed when it comes to a leak in your boiler, it is not going to be good. It is very important that you seek help from an engineer as soon as you notice water leaking from your boiler. This is an issue that can cause some serious problems within your home, so getting it seen to early is one of the best ways to avoid this.

There are several different reasons why you may be experiencing a leaking boiler. If your boiler is old, covered in corrosion, and simply looks beyond repair, then it is time to replace it. You can often get a free quote from an engineer regarding the different boiler models they have and the cost of installation in your home.

Why Is My Boiler Leaking Water?

There are several different causes for a boiler leaking, and these can determine how much it will cost to be fixed or whether it can be fixed at all.

It is important that you call an engineer as soon as you notice your boiler leaking to reduce damage and ensure that there are no other issues, such as corrosion of other essential pipes and equipment.

Here are some of the most common issues when it comes to boilers leaking water:

Corrosion to Pipe Fittings

In most cases, the pipes that are immediately underneath your boiler are the main cause of leaking. Boiler leaks can often appear as a result of corrosion to the pipe underneath the device, which can happen over time or as a result of badly installed pipes.

Older boilers will experience leaking through this over time as the water in the device combined with the metallic debris will cause natural corrosion to the copper pipes. This will lead to small gaps in the pipework, which will cause water (and sometimes fuel) to start leaking out.

If you have a new boiler that has just been installed, then corrosion probably isn't the issue here but rather a poor installation job by the engineer. This doesn't necessarily mean that it is entirely their fault, but if this is the case, the company should send someone out as soon as possible to resolve the issue and make sure everything is secured within the boiler as it should be.

This is why it is vital that you use a reputable boiler and electrical company that has qualified engineers on hand for all services.

Too Much Boiler Pressure

Boiler leaks can also be caused by too much pressure in your boiler. It is possible that you don't really understand how boilers and pressure fit together, despite the fact you've heard the statement so many times, but don't worry, you're not the only one. You can also see our guide on what to do if your boiler is losing pressure.

Essentially, boilers (like many other devices - and people!) are not equipped to handle too much pressure. This is what can cause your boiler leaking water. Too much pressure in a boiler simply means that there is too much water being used, which can result in leaks.

If the pressure release valve (PRV) is too high on your boiler, then it will start to leak water as a way to alleviate this for itself.

Think about yourself when you feel under pressure - chances are it will be released through leaking water (aka. tears). This is essentially how your boiler operates, and leaking water can be a sign that the boiler pressure valve is too high, and it can't cope.

Sometimes the boiler pressure may be too high that internal parts of the boiler have failed or broken, which results in a leak.

It is possible and very easy for you to check whether your boiler is being put under too much pressure, and you should do this as soon as you notice it leaking to avoid internal damage. Most boilers will have a pressure gauge on the front of the device (often located right next to the pressure valve).

There will be a green marking that indicates the right levels of pressure for your boiler model. If the dial is too far away from this, then you are dealing with an under-pressure leaking boiler. This can be treated by bleeding the system, which you can do without the help of a heating engineer, by turning the temperature valve on your radiators.

Corrosion and General Wear

Boilers aren't made to last forever, so if you notice your boiler leaking, then it could be a sign that it needs to be replaced. Using an old gas boiler or similar model can actually be quite dangerous, especially when it starts leaking water and possibly fuel.

It is likely that over time the copper pipes of your boiler have been corroded, which will have caused holes. This is why the boiler leaking water is now an issue for you, as water is coming out through the pipes.

Make sure to call out an engineer to check out your boiler, even if it is an old gas boiler model, as they will be able to determine how much damage has been done and what repairs can be made. You will then want to get a quote to see the price of a new boiler and how much it will cost to replace your boiler. Then it's time to start saving!

Faulty Heat Exchanger

The heat exchanger of your boiler is the most expensive part, so this can be one of the worst things to cause a boiler leaking water.

The heat exchanger can fail, crack, or come to other damage in old or low-quality boiler models, which can cause a lot of issues in your home. This is why it is very important for you to use a respected and qualified boiler company when getting a device installed, but this advice comes too late for those dealing with this issue right now.

It is not possible for you to determine whether you are having issues with the boiler heat exchanger unless you are a qualified engineer. This means you need to call out a gas safe registered engineer who can diagnose whether this is what's causing the boiler leaking water.

If it is a case of a faulty heat exchanger, then it can be replaced by a gas safe registered engineer. However, as this part costs so much, it may be better value for you to get a replacement boiler instead.

The engineer will be able to give you a quote for both the part and boiler replacement so you can determine which is the best value option.

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Leaks from Internal Parts and Seals

Over time, it is possible for the seals and pump in your boiler to corrode over time. This can prevent them from working as well as they used to and will leave your boiler victim to internal damage, which can result in a safety issue for your home.

Internal leaks can cause a boiler leaking water at quite a rapid rate, so you will need to call an emergency engineer out if you notice this issue. They will be able to take a look at the internal parts of your boiler to see what is causing the water and fuel leak.

Is Boiler Leaking Water Dangerous?

In some cases, a boiler that has a leak can be dangerous, but this is only for older models. Your boiler will not explode or cause your house to fall down because it has a leak.

It is often just an inconvenience that can get in the way of your daily routine and will undoubtedly impact how happy you feel in your home.

However, this doesn't mean that this issue shouldn't be dealt with as quickly as possible.

This is especially the case for boilers that are connected to central heating, as it can cause this to stop working as well.

If you have old appliances in your home, then a leak can be a very dangerous matter, and you should get in contact with your boiler provider as soon as possible to prevent any further damage.

In most cases, those with older boilers will need their full central heating and water system replaced as this will be cheaper than getting certain parts mended.

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