What is the cost of a boiler replacement?

Key takeaways

• Replacing a boiler typically costs £1,000–£3,000 for a combi boiler or £1,500–£4,000 for a regular or system boiler, excluding installation fees which can range from £500 to £2,500 depending on complexity.
• A straightforward boiler replacement can take as little as one day, while more complex installations, such as system upgrades or relocations, may take 2-3 days.
• Although heat pumps have a higher upfront cost (starting at £5,450 after grants), they provide up to 500% efficiency, lower energy bills, and reduced carbon emissions, making them a forward-thinking replacement for gas boilers ahead of future bans.

Getting a new boiler for your home can be a stressful experience, especially in an emergency. With different types of boilers to choose from, such as combi boilers, regular boilers and system boilers, and confusing misinformation surrounding costs, it’s no wonder why so many people put off replacing their boiler until the last possible moment.

However, getting a new boiler installed as quickly and efficiently as possible is important, especially during the colder months when you need heating and hot water more than usual!

Here, we’ll explore how long it takes to replace a combi boiler and traditional boiler, the cost of different types of heating systems for your home and what other factors can influence the price to help you better understand the process. We’ll also explore why a heat pump could be the ideal replacement for your boiler.

Combi boiler replacement

A combi boiler is popular in small residences, such as apartments, thanks to its ability to provide hot water and heating instantly on-demand, without the need for a bulky hot water cylinder, from a single unit.

How much does it cost to replace a combi boiler?

On average, a new combi boiler can cost anywhere between £1,000 to more than £3000 depending on the brand. Budget combi boilers will cost less while more premium boilers will be more expensive and likely last longer. 

It’s important to remember that this cost is only for the boiler itself and not the installation, annual maintenance and servicing, or repair costs. Simple replacements, where the boiler is of the same type and installed in the same location, typically cost around £500. In contrast, more complex installations, such as relocating the boiler or upgrading the system, can exceed £2,000.

How long does it take to replace a combi boiler?

If you’re replacing a combi boiler with the same system, the installation should be completed in a few hours. However, if you’re replacing an old boiler with the more modern combi boiler, the installation process is extensive as it involves the full removal of your old boiler and water cylinder, new pipework installed into the existing boiler location and installation of the boiler itself. This work can take a couple of days and can cost an additional £500 to £2000.

How long does a combi boiler last?

With proper maintenance, combi boilers are designed to last around 10-15 years, so they aren’t something that need replacing too often.

Combi boiler vs heat pump replacement

When replacing a combi boiler with a heat pump, the installation process is usually more complex. Heat pumps often require additional modifications to your existing heating system, such as new pipework or radiators and typically come with a higher upfront cost. 

However, with the £7,500 Boiler Upgrade Scheme grant, these additional expenses can be significantly reduced, making the cost of installing a heat pump (from £5,450 after the grant) more comparable to replacing your existing heating system with a new combi boiler than you might expect.

While the upfront cost of installing a combi boiler may be lower than a heat pump, heat pumps are significantly cheaper to run over time. Modern condensing combi boilers typically operate at 90-95% efficiency, meaning they convert 90-95% of the energy from gas into heat. 

In contrast, modern air-to-water heat pumps, like the Aira Heat Pump, offer a Coefficient of Performance (COP) between 4 and 5 under standard conditions. This means for every unit of electricity consumed, they generate 4 to 5 units of heat, delivering 400-500% efficiency compared to the energy input. All this efficiency equates to lower energy bills. Up to £560 per year lower when combined with a heat pump tariff like Aira Zero. 

Furthermore, while a combi boiler typically lasts 10-15 years, heat pumps offer a longer lifespan of 20 years or more, making them a more durable and long-term heating solution.

Compare a heat pump vs a gas boiler to see which is the right system for you.
 

Regular and system boiler replacement

Regular and system boilers are typically classed as “traditional boilers” and are powered by fossil fuels like oil or gas. They use a separate water cylinder or water tank, often found in an airing cupboard or the loft, that stores hot water ready to use. 

These systems aren’t instant like combi boilers and are becoming less popular as more efficient alternatives, like combi and heat pump systems, become more sought after. 

How much does it cost to replace a traditional boiler?

On average, the cost of replacing a regular or system boiler can range between £1,500 to £4,000 depending on the type and brand of boiler chosen. Budget models will be on the lower end of this scale, while premium models, with higher efficiencies and better longevity, will be more expensive.

Similar to a combi boiler, the price quoted for the boiler itself doesn’t include installation, servicing, or any potential repairs.

The cost of installation can vary based on complexity. For a simple replacement where the new system is installed in the same location as the previous one, installation costs usually start around £500. However, if the system requires a more complex installation, such as upgrading pipework or relocating the boiler, costs can rise to £2,500 or more.

How long does it take to replace a boiler?

Replacing a traditional boiler with the same type is typically a straightforward process that can be completed within a day. However, if you're upgrading or relocating the system, the installation can take a couple of days. This includes removing the old boiler, updating pipework, and setting up the new system.

How long does a boiler last?

A regular or system boiler typically lasts 10-15 years, similar to a combi boiler. Regular maintenance is important to extend the lifespan of these systems, but once they reach the end of their life, you’ll likely need to replace them with a newer, more efficient model.

Boiler vs heat pump replacement

While the UK government's original plan to phase out gas boilers in new homes starting in 2025 has been delayed, many homeowners are considering heat pumps as a replacement to their gas boilers. Why? Because while the installation of a heat pump can be more complex than replacing a traditional boiler, it offers significant long-term cost-saving benefits. 

Heat pumps typically require modifications to your existing heating system, such as upgrading radiators or adding new pipework, which can increase upfront costs. However, with the £7,500 Boiler Upgrade Scheme, the overall cost of installing a heat pump (around from £5,450 after the grant) becomes more comparable to replacing a regular or system boiler.

Heat pumps are also far more energy-efficient than gas boilers, offering 400-500% efficiency, while traditional boilers operate at about 90-95% efficiency. This translates into lower energy bills, with savings of up to £560 per year when paired with a heat pump-specific tariff like Aira Zero. 

And, while gas boilers last around 10-15 years, heat pumps have a lifespan of 20 years or more, making them a more durable choice. Though the upfront costs may be higher, the long-term savings and government incentives make heat pumps an excellent alternative for replacing gas boilers ahead of the eventual ban. 

What can Influence the Cost of a new Boiler?

As we’ve seen, the cost of replacing boiler with another boiler can range drastically, along with the cost of installation too. Below is a breakdown of the most common factors that influence the cost of the boiler replacement so you’ll know, roughly, what to expect:

• The boiler itself – as discussed above, this can cost between £1,000 to £3,000 for a combi boiler or £1,500 to £4,000 for a regular or system boiler.
• Boiler installation – this will depend on how long the job will take and how complex it may be and can range from £500 and £2,000.
• Vertical flue cost – the vertical flue is the pipe that leads from the boiler to the outside of your home. A horizontal flue is the standard pipe for most boilers and won’t cost any extra, but if you require a vertical flue, which is more work, this can cost more.
• Plume kit – if your boiler’s flue is too close to a window or a door, you’ll need a plume extension kit installed.
• Gas pipe upgrade – many gas pipes in older homes will need to be replaced with more modern copper piping with a larger width to meet regulations.
• Relocation – if you want to move your boiler to a more convenient spot, this can incur a hefty charge as it will need a lot of physical labour, pipework, new fixtures and fittings and the repair/renovation of the old spot.
• Controls – with a new boiler often comes new controls installed, too, especially if you’re replacing an old boiler with a more modern combi boiler.

Save money with an Aira Heat Pump

Replacing your boiler is an expensive project and something that fills many homeowners with dread. An alternative to the traditional boiler is an air to water heat pump like the Aira Heat Pump. 

Aira Heat Pumps are four times more efficient than a gas boiler, producing 100% less carbon emissions and brings in 33% savings on energy bills when combined with a clean energy tariff like Aira Zero. They’re also easier and cheaper to maintain and can last about 25% longer than boilers.

Explore how much is a heat pump and decide if a heat pump is the right option for you.