How Long Combi Boilers Last: Based on Age, Use and Condition

Friday 11th March 2022
by Homeforce

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Fri 11th March 2022

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Paying out for a new boiler can be a terrifying thought not to mention the disruption to your daily life. Freezing cold showers in winter is no one’s idea of fun! 

So it’s not surprising to discover many of us wonder how long does a combi boiler last? We’ve been maintaining boilers for many years, so in our helpful article, we will cover all your questions, how, when, and why, plus tips on how to prolong your boiler’s life.

First, we will hit the quick answer before we start discovering how long combi boilers last in a little more detail.

Although there is no set rule as to how long a combi boiler lasts, in general, it should last around 15 years. It could be longer if they are serviced regularly and well maintained. It will also depend on the brand, the quality of your combi boiler, and other installation and daily use factors.

Combi boiler use vs life expectancy table

Assuming you carry out regular annual checks and maintenance on your boiler here’s a guide on how long you can expect your boiler to last from new.

Boiler UseExpected Lifespan
Minimal/Light Use15+ Years
Regular Home Use12-15 Years
Maximum/Heavy Use10-12 Years

If you’re considering servicing your own boiler, then here’s the boiler servicing guide you need to read.

Ok so we can more easily understand how long a combi boiler lasts, let’s get into exactly what it is. 

What is a combi boiler?

The word ‘combi’ is short for combination and is a water heater and a central heating system all in one unit.

A combi boiler will heat up hot water as soon as your hot tap is switched on, which gives you hot water ‘on-demand.’ 

Combi Boiler Controls

The main plus point of a combi boiler is that you don’t need a storage tank which is a requirement in a standard conventional boiler. 

How a combi boiler works

A combi boiler warms your home through a system of radiators placed throughout the home and as we mentioned previously, hot water is available almost immediately after turning on your hot water tap. 

There is no need for a hot water cylinder or a cold water tank. 

Ok so with a brief description of a combi boiler in mind, let’s head right in and find out how often a combi boiler needs to be replaced.

How often a combi boiler should be replaced 

As your combi boiler ages, as with any appliance, it can become less efficient and unreliable. 

There are numerous crucial electronic and mechanical parts in a combi boiler that are required to heat water at the turn of a tap. So it stands to reason that working parts which are used daily, every time you turn on your tap, can become worn.

As a combi boiler gets older it might be time to think about a replacement. As we found out previously, most combi boilers have a lifespan of around 15 years, not what if your boiler is only 10 years old? 

Read on to find out more. 

Should I replace my 10-year-old boiler?

Replacing your combi boiler too late means you could end up without water and heating. It can be tricky knowing when to get rid of one which is approaching the end of its life, but hasn’t quite got there yet! 

The above table is a guide, but replacing an older boiler too soon could mean you have got rid of a perfectly good boiler that may have lasted a good few years more.

When should I replace a combi boiler? 

We would all want to know the best time to consider replacing our boiler. So what should you look out for? 

  • Unusual noises: If your boiler is showing signs of tapping, hissing, clanging or groaning, it might be a sign that your boiler is ready to be replaced. The noises might come from the boiler itself pipes, or from your radiators. So check regularly for any unusual noises.
  • Sludge build-up: Even new combi boilers can fill with a sludge build-up, known as magnetite. This can add to any other problems your combi boiler has and can significantly reduce its performance.

    This build-up contains limescale which can damage your boiler. To prevent magnetite building up, the heating system can be flushed through to remove the sludge and allow water to pass through the pipes more freely. However, in very bad cases, it could mean you will need to buy a new boiler.
  • Frequent breakdowns: Although having to call out an expert boiler engineer for an occasional breakdown might not be a reason to buy a new one if you find your boiler breaks down more than once a year it might be time for a replacement.

    Constant call-outs and expensive repairs could end up costing more in the long run than buying a new boiler. Many of the best home appliance repair specialists offer boiler plans which can help to spread the cost. However, if your boiler has broken down too many times, it might be safer and more economical to get a new combi boiler. 
  • High energy bills: Older combi boilers are not as efficient as newer models. Older ‘G’ rated models are only around 70% efficient, whereas the new ‘A-rated types can be over 90% efficient in terms of energy. Replacing your boiler could save you up to £350 per year. 
  • Doesn’t support smart technology: Many of the newer boilers support smart technology which allows you to control heating at the touch of a smart device, such as an iPad or phone. This gives you easy access to controlling your combi boiler and your heating system wherever you are and at whatever time of day or night. This can help you run your heating more efficiently and help to save costs on energy bills. 
  • Check flame is still blue: Another reason you might decide to replace your boiler is if the boiler flame is no longer blue in colour. If it’s burning either orange or yellow, it means the combi boiler isn’t working properly and could result in dangerous carbon dioxide production.

    If this happens then you will need to call out an experienced heating engineer straight away. It could be an issue that can be easily rectified but it could be a sign that your combi boiler needs replacing. 

So how do you make sure your combi boiler lasts as long as it can before replacing it?

Combi Boiler Pressure Gauge

How do I extend the life of a combi boiler? 

Annual service

It’s now a requirement for most combi boilers to insist on an annual service to comply with the manufacturer’s guarantee or warranty. 

Service history for your boiler is crucial or your guarantee may become invalid. 

Always hire a qualified gas engineer to carry out the service. They are known as Gas Safe Registered Engineers so always check credentials before an annual boiler service. You can either ask the engineer to show you his ID or do a quick online check at Gas Safety Register 

It’s also worth understanding that legally only a registered gas safety engineer can remove a boiler case in order to carry out an inspection, or an annual check.

So for those of you wondering how long a combi boiler lasts, you might also be looking into the cost, if yours is ready to replace. 

Read on to discover more. 

How much does a boiler service cost? 

Generally expect to pay between £60 and £120 for an annual boiler service. The cost does vast and will mostly friend on your location and the type of boiler you have. 

What can I do to extend the life of my combi boiler? 

So although you can’t remove the casing of your boiler, is there are any maintenance and care you can do to extend the life of your combi boiler?

Keep pipes well insulated 

Keeping pipes well insulated is a good way to extend the life of your combi boiler. Lagging the pipes that you might find in your loft or garage means you can help to protect against winter weather. It’s often in winter when pipes can split and cause major problems including leaks. 

Lagging is available fairly cheaply online or from DIY stores. 

Test run during summer 

As a boiler has many different working parts needed to heat your home and water, they don’t benefit from being unused for long periods of time. 

This is often why issues with combi boilers and other types of boilers happen in late autumn when the system is started to be used again after summer. 

Although hot water will still come on demand from a ‘summer setting’, it is useful to run your system occasionally during cooler summer days. 

This helps stop the build-up of sludge and other debris building up in your radiators and around other components. 

Bleed your radiators 

Air build up in radiators is another common problem which you can manage during the year to help extend the life of a combi boiler. 

Most combi boilers do have an automatic air vent or AVV which helps to dispel air that might find its way into the radiators. 

But it will help if you routinely bleed your radiators with a radiator key. 

Gas Boiler Pipework

How much does a new boiler cost? 

Similar to how much a boiler service costs, the same factors and others will apply to the cost of a brand new combi boiler.

It will of course depend on the brand of appliance you choose and also the type of installation. 

Types and sizes of combi boilers can vary in price. You will also need to factor in the labour cost required to install it.

In general, a combi boiler for a smallish home could cost anywhere between £500 to £1500 depending on the type you decide to buy.

For example, a new combi boiler for a small home could cost anywhere from £600 to £1,500, depending on the particular model

And to finish on…

We hope that has given you some tips and advice on how long a combi boiler lasts and some simple steps you can take to maintain your boiler.

Here at Homeforce, we are specialists in maintenance plans and combi boiler repair. 

By taking out a Homeforce boiler plan you can have the peace of mind that in the event of any boiler breakdown, we will have you back up and running again quickly and efficiently. 

We offer a U.K. wide network of qualified engineers to fix your boiler without any more costs outside of your boiler plan. Get in touch here to find out more.

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