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Last updated: 17th May, 2024


New Boiler Cost UK: How Much is a New Boiler in 2024?

New Boiler Cost UK: How Much is a New Boiler in 2024?
Table of Contents

Key takeaways

  • New boiler costs can range from £500-£3,500 before installation.
  • A correct boiler size and professional installation are crucial.
  • Funding options are available to manage the investment.
  • Government initiatives such as the Boiler Upgrade Scheme and ECO4 can significantly reduce the financial burden of boiler replacements for qualifying homeowners, offering grants that may cover as much as £7,500!

The cost of a new boiler depends on the installation type and many different variable costs. On average the cost of a new boiler installed can range between £1,500 and £4,500.

Investing in a new boiler is a significant but worthwhile decision for homeowners and landlords, blending immediate practicality with an investment in the future. 

New boiler cost is something that can vary broadly, typically ranging from £1,000 to over £4,500 influenced by choices in technology, type, and size.

This price range accommodates everything from straightforward replacements to comprehensive system upgrades, such as switching from old back boilers to high-efficiency combi boilers, which may require extensive changes like pipework modifications.

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New Boiler cost also depends on factors like brand reputation, installation complexity, and regional pricing within the UK.

When selecting a new boiler, it's essential to consider the heating requirements of your property to ensure you choose a model that aligns perfectly with your needs.

Compliance with safety standards is crucial; installations and maintenance should always be handled by Gas Safe registered engineers.

The investment of new boiler cost should be viewed positively, as it not only enhances home comfort but also increases energy efficiency, reducing overall household expenses in the long run. Fortunately, various financing options, grants, and payment plans are available to make this important upgrade more accessible, ensuring that your home remains warm and efficient without placing undue financial burden on you.

How Much Does a New Boiler Cost in the UK?

When homeowners consider the expenses tied to maintaining their UK residences, updating or replacing a boiler is a significant consideration.

We will delve into the 'boiler replacement cost', covering the various factors that influence these costs, including installation complexity and additional elements like chemical cleanse and boiler filter.

Efficient heating systems are vital for comfort and energy savings, and the costs involved are impacted by various factors that are worth exploring.

The average cost of a new boiler installed can range between £1,000 and £4,500.

New Boiler Type

Cost (excl. Installation)

Cost (inc. Installation)


Combi swap

£500 - £3,000

£1,500 - £4,500

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System boiler

£550 - £3,500

£1,700 - £4,000

Get a quote

Conventional boiler

£600 - £3,500

£1,700 - £4,000

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Electric boiler

£550 - £2,500

£1,600 - £3,500

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Other system install costs

System type

Price (inc. Installation)


Combi conversion

£1,500 - £4,500

Get a quote

New full system install

£3,000 - £6,000

Get a quote

Back boiler conversion

£3,000 - £5,000

Get a quote

(all tables are intended as a guide only)

Why is a Boiler So Important?

In the UK, a boiler is central to a home's heating system, providing the necessary warmth and hot water throughout the year.

The weather can dictate a heavier reliance on a functioning boiler, especially during the colder months, making an efficient system paramount for both comfort and reducing energy costs.

Do I Need A New Boiler?

Deciding whether to invest in a new boiler hinges on several factors.

Consider the age and efficiency of the current unit, any frequent breakdowns, and the escalating costs of repairs and energy. 

If a boiler is older than 15 years, it may be prudent to replace it to enhance efficiency and reliability!

How Do I Get a New Boiler?

Getting a new boiler with iHeat is fast and easy as our industry revolutionising approach places the customer and their needs at the centre of all that we do.

iHeat offers free, fixed price, online quotes in literally seconds, on our range of premium, money saving boilers, with installation as fast as next day!

New Boiler Cost in 2024

The cost of installing a new boiler in the UK can range considerably.

In 2024, homeowners might expect to pay between £1,600 for a basic system boiler with a 5-year warranty to upwards of £4,000 for a comprehensive replacement, including advanced models with extensive warranty periods.

Factors Affecting New Boiler Cost

Several elements influence new boiler cost. These encompass-

  • Type of Property: Smaller flats may require less powerful boilers compared to large houses.

  • Location: Costs can vary regionally across the UK, typically higher in London.

  • Model and Type: High-efficiency models and different types (combi, system, or conventional) can impact price.

  • Additional Costs: Extras like thermostats or specialised controls add to the overall expense.

Installation Work and Actual Boiler Unit - Costs Explained

Installation expenses are twofold:

Boiler Unit:

  • Type: Combi, Heat-only, or system

  • Model: Premium brands cost more

  • Warranty: Longer warranties may raise the price

Labour and Installation:

  • A straightforward replacement generally costs less than an installation that requires moving the boiler to a new location or significant pipework modifications.

  • Labour costs are affected by the duration and complexity of the installation.

  • Materials and any additional work, like upgrading radiators or fitting new controls, can also lead to higher expenditure.

Understanding the total cost of a new boiler in the UK requires consideration of the boiler unit, the complexity of the installation process, labour charges, and any ancillary materials.

Accurate quotations and professional advice are the keys to ensuring a successful and cost-effective boiler replacement.

What Are the Different Types of Boiler and Which Boiler is Perfect for What Type of Property?

different types of boilers

When choosing a boiler for home heating, it's important to understand the various types available to find the best fit for your needs:

New Combi Boilers

Combi boilers are compact units perfect for smaller homes or apartments with limited space.

They provide both heating and hot water directly from the boiler without the need for additional tanks or cylinders. Ideal for properties with one bathroom, as they can struggle to meet high simultaneous water usage demands typical in larger households.

combi boilers

New System Boilers

System boilers are well-suited for homes with higher hot water demands, such as medium to large-sized properties with multiple bathrooms.

These boilers require a cylinder to store hot water but have major heating components built into the unit, making installation neater and often quicker.

They're a great option for homes with adequate space to house a hot water cylinder without the need for a cold water tank, balancing space with functionality.

system boilers

New Conventional Boilers (Heat-Only)

Also known as regular or heat-only boilers, these are best suited for older, larger homes that have traditional radiator systems and enough space for a separate hot water cylinder and a cold water storage tank.

Ideal for properties with several bathrooms, these boilers can efficiently manage multiple hot water outlets being used simultaneously, making them perfect for larger families.

heat only boilers

New Electric Boilers

Electric boilers are an eco-friendly alternative that works best in smaller properties like apartments or small houses, particularly where gas is not an option. They are highly efficient, easy to install, and don't produce emissions onsite.

These units are particularly attractive in areas where electricity comes from renewable sources, aligning with green energy initiatives.

electric boilers

New Biomass Boilers

Biomass boilers are suited for rural properties or homes with access to space for storing fuel like wood pellets, chips, or logs.

These boilers are a sustainable choice, using biofuels to produce heat and hot water, thus reducing reliance on fossil fuels. Ideal for homes looking for an eco-conscious heating solution that can accommodate the larger footprint and storage needs of biomass fuel.

biomass boilers

New Condensing Boilers

Condensing boilers fit any property type from small flats to large detached homes.

They are highly efficient as they capture heat from exhaust gases that would otherwise be lost via the flue. This efficiency makes them suitable for anyone looking to reduce their energy consumption and lower their heating bills.

Each boiler type offers unique advantages depending on your home's size, layout, and hot water needs, ensuring you can choose the most efficient and suitable system for your living situation.

condensing boilers

How Much Does a New Combi Boiler Cost?

When assessing the cost of a new combi boiler, it's essential to consider not only the initial purchase but also the installation expenses and the potential impact on energy bills.

What is a Combi Boiler and Costs?


A combi boiler, short for 'combination boiler', is a high-efficiency water heater and a central heating boiler, combined within one compact unit. 

The price of a combi boiler generally ranges from £1,800 to £4,000, with factors such as brand, size, and features playing a pivotal role. The installation of a combi boiler adds to the cost, and this is highly variable based on the complexity of the job and the rates of the installer.

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advantages of a combi boiler

Advantages of a New Combi Boiler

  • Energy Efficiency: Combi boilers are known for their energy efficiency, which can potentially lead to lower energy costs.

  • Hot Water on Demand: They provide hot water instantly, negating the need for a separate hot water cylinder.

  • Space-Saving: The compact size of combi boilers makes them ideal for smaller homes, as they save valuable space.

  • Central Heating System: These boilers are adept at serving as the central component of a home's heating system.

disadvantages of a combi boiler

Disadvantages of a New Combi Boiler

  • High Demand Limitations: During high demand, combi boilers might struggle to provide sufficient hot water, which is a drawback for larger homes.

  • Cold Water: If the boiler breaks, cold water can be a significant inconvenience, since there is no hot water tank as a backup.

  • Installation Cost: The initial installation cost can be high, though potential savings on energy bills can mitigate this over time.

How Much Does a New System Boiler Cost?

Selecting a new system boiler involves considering its purchase and installation costs, and the potential benefits in energy efficiency and space utilisation. Here's a detailed look at the financial implications and the pros and cons of system boilers.

What is a System Boiler and Costs?


A system boiler directly heats your central heating system and produces hot water for a storage cylinder. They tend to be easier and less expensive to install than conventional ones because they incorporate many of the major individual heating and hot water system components. 

As of 2024, a new gas system boiler cost generally falls around £2,700, while an oil system boiler may cost closer to £3,163.

The costs may rise if you opt for more advanced models or include additional features or controls. Basic models with a 5-year warranty start at about £1,600, and high-end system boilers can reach approximately £2,500, including installation.

  • Typical Cost Ranges for System Boilers:

    • Basic: From £1,600

    • Average: Around £2,700

    • High-End: Up to £2,500 or more

  • Key Components Included: Central heating components, pump, and expansion vessel.

  • Installation: Simplified due to fewer components.

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advantages of a system boiler

Advantages of a New System Boiler

System boilers are beneficial for homes with multiple bathrooms as they provide a constant supply of hot water to any number of taps simultaneously. They are also:

  • Energy Efficient: Reduced heat loss and typically more efficient than conventional boilers.

  • Space-Efficient: Requires less space than traditional boilers since they don't need an upper tank.

  • Compatible with Solar Thermal Systems: Can be easily integrated with sustainable energy sources.

disadvantages of a system boiler

Disadvantages of a New System Boiler

However, system boilers also have drawbacks. They:

  • Require a Cylinder: A hot water tank is necessary, which can take up valuable space.

  • Do Not Provide Water on Demand: Unlike combi boilers, hot water isn't instant.

  • Initial Cost: Higher upfront costs compared to combi boilers, due to the cylinder and additional components.

How Much Does a New Heat-Only Boiler Cost?

Navigating the complexities of installing a new heat-only boiler involves considering both the unit price and installation costs. This section delves into what consumers can expect to pay for a heat-only boiler, its benefits, and potential drawbacks.

What is a Heat-Only Boiler and Costs?


A heat-only boiler, also known as a conventional boiler or regular boiler, is a traditional heating system that typically works alongside a separate hot water cylinder and cold water storage tank, often installed in an airing cupboard and loft respectively. 

For a new heat-only boiler, costs may vary significantly but typically range from £650 to £2,150 for the unit itself. Installation costs can increase this figure, depending on the complexity of the job and whether additional components, such as new radiators or pipework, are needed.

It's not uncommon for installation to incur further expenses of approximately £500 to £1,000. However, these figures can differ based on geography, the specific model of the boiler, and the installer's pricing.

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advantages of a heat only boiler

Advantages of a New Heat-Only Boiler

Heat-only boilers are renowned for their reliability and aptitude in managing the heating and hot water demands in homes with high water usage. They cater well for homes with multiple bathrooms where simultaneous hot water use is common. 

Since they operate at low pressure, these boilers are less prone to leakage compared to high-pressure systems. Additionally, with a separate hot water cylinder, heat-only boilers offer a substantial supply of hot water on demand, making them a robust solution for larger households.

disadvantages of a heat only boiler

Disadvantages of a New Heat-Only Boiler

The primary disadvantage of conventional boilers lies in their size and the additional space required for the hot water cylinder and water tanks. For smaller homes or properties with limited space, this can be a significant issue. 

Another factor to consider is that when replacing an old and inefficient boiler, the initial outlay for a heat-only boiler can be relatively high when including installation charges.

Furthermore, while reliable, these systems may not be as energy-efficient as newer condensing boilers, potentially leading to higher running costs if the anticipated hot water use is not considerable.

How Much Does a Back Boiler to Combi Boiler Conversion Cost?

The transition from a back boiler to a modern combi boiler can significantly enhance energy efficiency and save space by relinquishing the need for a hot water cylinder.

Things to Consider

When examining the costs involved in a back boiler to combi boiler conversion, it's essential to contemplate both the property size and the complexity of the job at hand. The larger the property, the more substantial the combi boiler needed, which can impact the overall cost. Installation cost normally includes labour and may vary based on location and the engineer's experience.

Additionally, there might be indirect additional costs, such as the removal of old systems and the potential need for new pipework.

It's prudent to anticipate some variation in the quotes you receive. A customary installation typically ranges from £2,800 to £4,500, depending on various factors including the brand and capacity of the boiler.

Properties with straightforward conversion requirements will generally fall at the lower end of this spectrum, whereas those necessitating extensive modifications will incur higher costs.

Can I change my old boiler to a new combi boiler?

Converting to a combi boiler is feasible for most properties with a back boiler. A combi boiler operates proficiently in small to medium-sized homes, effectively producing hot water on demand without reliance on a storage tank. 

However, homes with higher hot water demands might need to carefully assess whether a combi boiler will meet their needs.

During conversion, the back boiler is removed and the combi boiler is installed in its place.

This process might require rerouting gas pipes and removing obsolete components, like the hot water cylinder, which adds to the complexity of the task. 

The investment in a modern combi boiler system is not just financial; it represents a commitment to improved energy efficiency which can lead to a reduction in heating bills over time.

New Boiler Cost - Best Brand Comparison

Choosing the right boiler can be integral to ensuring efficient heating and hot water in one's home. With a variety of brands offering distinct 2024 models that promise reliability and performance, it's important to compare the best options available.

New Vaillant Boiler


Popular Models:

ecoFIT Pure Regular:

Known for its compact design, this model is ideal for smaller spaces and can efficiently meet the hot water demands of larger households.

ecoTEC Plus Combi:

Offers a range of power outputs suitable for different home sizes, noted for its energy efficiency and reliability.

Vaillant Brand Popularity:

Vaillant is favoured in the UK for its commitment to sustainability and energy efficiency. The brand is well-regarded for its German engineering quality, robust build, and innovative features that cater to a wide range of domestic heating needs.

New Worcester Bosch Boiler


Popular Models:

Greenstar 28CDi Compact:

A compact model that delivers top-notch energy efficiency, it's perfect for smaller homes needing high-efficiency heating and hot water.

Greenstar 8000 Life:

This model stands out with its modern design and high performance, suitable for larger homes with significant hot water demands.

Worcester Bosch Brand Popularity:

Worcester Bosch is synonymous with reliability and longevity in the UK market. Its boilers are celebrated for their excellent build quality, comprehensive warranty options, and strong after-sales support, making them a preferred choice among homeowners.

New Viessmann Boiler


Popular Models:

Vitodens 050-W Combi:

A great option for its price-performance ratio, offering high efficiency in a compact size ideal for average-sized homes.

Vitodens 100-W Combi:

Known for its durability and quiet operation, it's suitable for medium to large homes with its adaptable power settings.

Viessmann Brand Popularity:

Viessmann is recognised for high-quality engineering and cutting-edge technology in boiler systems. The brand's focus on energy efficiency and sustainability makes its products highly popular among environmentally conscious consumers.

New Ideal Boiler


Popular Models:

Logic+ Combi:

Offers impressive energy efficiency and compact design, making it a smart choice for smaller homes.

Vogue Max Combi:

Features premium construction and advanced technology, providing dependable performance and long-term reliability.

Ideal Brand Popularity:

Ideal is known for delivering cost-effective heating solutions without compromising on quality. Its boilers are appreciated for their ease of installation, user-friendly operation, and robust warranty offers.

New Alpha Boiler


Popular Models:

E-Tec Plus Combi:

A practical choice for everyday use, offering reliable performance and straightforward operation.

Evoke Combi:

Features a compact design and efficient operation, aimed at maximising home comfort while being budget-friendly.

Alpha Brand Popularity:

Alpha is renowned for providing good value with essential features. The brand's focus on practicality and affordability makes it particularly attractive to those seeking economical yet reliable boiler solutions.

New Boiler Cost - Best Brand Comparison


Notable 2024 Model

Warranty Length

Noteworthy Features

Avg cost


Vaillant ecoTEC Series

Up to 10 years

User-friendly controls, advanced safety

£1,000 - £3,500

Worcester Bosch

Worcester Greenstar Series

Up to 12 years

Energy-efficient, innovative technology

£1,400 - £3,000


Viessmann Vitodens Series

Up to 10 years

Premium materials, leading-edge tech

£1,200 - £3,000


Ideal Logic Max

Up to 10 years

Cost-effective, reliable safety features

£1,000 - £2,500


Alpha E-Tec

Up to 7 years

Simple operation, efficient performance

£1,000 - £2,500

(guide only)

Benefits of New Boiler Installation

As households aim to become more energy-efficient, new boiler installation presents a clear path to achieving that goal. Through improved boiler efficiency and advanced heating controls, homeowners can enjoy not just warmth but also long-term savings and an enhanced property value.

New Boiler Efficiency

new boiler efficiency

Modern boilers are engineered for superior performance, with energy efficiency ratings climbing significantly compared to older models. These advancements translate to less fuel consumption and better heat distribution throughout the property. 

Enhanced features, like smart thermostats and smart radiator valves, grant finer control over heating, which conserves energy without sacrificing comfort.

New Boiler Long Term Savings

Installing a new boiler can manifest as a cost-effective move over time. Although there is an initial outlay, the reduction in energy bills due to higher efficiency means savings accrue each month.

Furthermore, boilers that come with a warranty provide peace of mind, reducing potential costs associated with maintenance and unexpected repairs.

  • Annual Energy Savings: It's not uncommon for efficient systems to slash energy bills by a considerable margin.

  • Maintenance Costs: New installations typically feature lower upkeep costs, benefiting from the latest design improvements.

Increase Value of Property with a New Boiler

A new boiler can bolster the desirability and value of a home. Prospective buyers often lean towards properties with modern, environmentally conscious heating systems. The installation of a heating system upgrade like an energy-efficient boiler could be a pivotal selling point, making a property more attractive in a competitive market.

  • Property Attractiveness: Enhanced with latest heating technology, a property stands out in the real estate market.

  • Investment Return: While upfront installation costs are part of the investment, the value added to the property can far outweigh these initial expenses.

New Boiler Cost in Different Areas 2024

uk boiler costs

New boiler cost and installation prices vary widely across the UK in 2024. Factors like regional living costs, demand, and labour rates significantly influence the overall expenditure.

London & South - New Boiler Cost Averages

In London and the South of England, boiler installation costs tend to be higher due to the elevated cost of living and labour. Installation costs, including labour, average between £2,000 and £2,500 for a new, budget combi boiler. High-end combi boilers can mount up to approximately £3,000.

Manchester/Liverpool & North - New Boiler Cost Averages

The North of England, encompassing major cities like Manchester and Liverpool, sees a moderate decrease in prices. There, homeowners might expect to pay between £1,800 and £2,200 for standard installation and labour relating to a new combi boiler.

Birmingham & Midlands - New Boiler Cost Averages

Birmingham and the surrounding Midlands area offer a midpoint in boiler installation and labour costs. New boiler installations generally range from £1,700 to £2,100, with potential variations based on boiler type and complexity of installation.

Scotland - New Boiler Cost Averages

Moving into Scotland, the cost of boiler installations maintains a relative consistency with the Midlands. Prices for installing a standard boiler including labour average between £1,650 and £2,000.

Wales - New Boiler Cost Averages

Wales presents similar pricing to the Midlands and Scotland for new boiler installations. The average cost falls into the range of £1,600 to £2,000, which includes the labour and installation fees.

These figures represent the cost landscape for boiler installations in different regions of the UK for 2024, highlighting a clear variation between the southern and northern areas.

iHeat Average New Boiler Cost - Different UK areas/regions


New Combi (inc. installation)*


£1,970 - £2,045

Wider South


Greater Manchester

£1,895 - £1,945

Wider North



£1,895 - £1,945





*(Intended as a guide only and based on replacing an existing combi boiler with an Alpha E-tec Combi Boiler)

iHeat boiler prices are stress-free, fixed price and literally takes 60 seconds, with installation dates as fast as the next day.

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When Should I Replace My Old Boiler with a New Boiler?


Deciding the right time for boiler replacement hinges upon several factors. A boiler's average lifespan is about 15 years; beyond this, it may become inefficient and costly to run.

They should recognise the symptoms of a boiler in decline which often include unusual noises, frequent breakdowns, and an increase in energy bills due to inefficiency.

Boilers can face issues such as rust and sludge accumulation which hinders performance; if a routine boiler service reveals such problems, they may consider a replacement.

Additionally, visible leaks are a clear sign the unit could be approaching the end of its viable life. An inefficient boiler not only raises operating costs but also impacts the environment negatively.

If they observe that the boiler struggles to heat the home or water adequately, or if repairs are becoming more frequent and expensive, these could be indications that it's time to upgrade. Here's a concise checklist:

  • The boiler is older than 15 years

  • Persistent breakdowns and faults

  • An uptick in energy bills despite regular use

  • Presence of rust and sludge within the system

  • Leakages from the boiler

  • Inadequate heating or hot water provision

Understanding when to replace a boiler is paramount for ensuring comfort, safety, and efficiency in a home. If they experience any of the above issues with their boiler, they should consider consulting with a professional to discuss the possibility of a new, more efficient system.

New Gas Boiler Alternatives

gas boiler alternatives

With the increasing need to reduce carbon emissions, homeowners are seeking efficient, low-carbon heating solutions. Transitioning from traditional gas boilers to alternatives can not only improve energy efficiency but also play a pivotal role in the journey towards a greener environment.

Heat Pumps

Heat pumps stand out as a renewable energy alternative to gas boilers.

Air source heat pumps extract warmth from the outside air, whereas ground source heat pumps harness heat from the ground.

These systems require electricity to run, but offer a significant cut in carbon footprint due to their high energy efficiency —often delivering up to four times the energy they consume.

Heat pumps are most effective in homes that are well insulated, as they operate optimally in maintaining a consistent temperature.

  • Installation Cost: High initial investment, but long-term savings on energy costs.

  • Energy Efficiency: Quite efficient, with a lower environmental impact than gas boilers.

Hybrid Heat Pump Systems

Hybrid heat pump systems integrate a heat pump with a traditional gas boiler. This combination provides flexibility, with the system primarily exploiting the heat pump's efficiency.

The gas boiler serves as a backup for colder periods or high demand. These hybrids help to facilitate the transition to renewable energy sources, bridging the gap for households not yet ready for a complete switch to full electric heating.

  • Carbon Emissions: Reduced emissions by utilising the heat pump most of the time.

  • Installation: More complex due to integration of two systems.

Hybrid heat pump systems can vary widely in terms of cost, due to numerous factors including model type, brand, and type of property.

Generally, hybrid heat pumps can cost anywhere from £6,000 for the unit and install to well over £10,000.

These high initial prices combined with the fact not every property type is suited to a hybrid heat pump system means any interested parties should carry out extensive research before committing to a purchase.

Electric Boilers

Electric boilers, especially electric combi boilers, are gaining traction as a reliable alternative to gas boilers.

While they have a lower carbon footprint when powered by renewable energy, the cost and environmental impact of electricity can vary. They convert nearly all the energy they use into heat and have no emissions on site, reducing the household carbon footprint.

  • Cost: Typically between £900 and £4,500 for purchase and installation.

  • Electricity Usage: 100% of the energy input is converted to heat, although the cost of electricity is higher than gas.

With their low-carbon benefits and increased energy efficiency, these alternatives to gas boilers are instrumental in shaping a sustainable future in residential heating. Transitioning to these systems supports the environment and can potentially lead to reduced long-term energy costs.

How Do I Know What Size New Boiler I Need?

Selecting the appropriate size of a boiler for one's home hinges on several pivotal factors, including the property's size, the heating requirements, and hot water needs.

It's about finding a balance between efficiency and ensuring you have enough hot water when you need it, without overspending on a system with excess power.

For a typical UK home, experts suggest allocating approximately 1.5 to 2 kilowatts (kW) per radiator. Consider this a starting point. Let's illustrate with some figures:

Number of Radiators

Ideal Boiler Size

1-10 Radiators

A combi boiler between 21-28kW is typically adequate.

11-15 Radiators

A 29-35kW combi boiler would likely suffice.

16-21 Radiators

One should consider combi boilers of 36kW and above.

When a property includes a hot water storage cylinder or tank, an additional 3kW is usually necessary to service this component of the system.

Therefore, accuracy in calculating the size becomes crucial, as an undersized boiler may lead to insufficient heating, while an oversized one could incur unnecessary costs.

Moreover, the decision also depends on the property size—larger homes necessitate more robust systems.

A terraced two-bedroom house, by contrast with a detached five-bedroom property, will have markedly different boiler size requirements.

In the case of combi boilers, which offer hot water on demand, the power output additionally defines the volume of hot water available at any given moment.

Hence, for homes with multiple bathrooms used simultaneously, homeowners may need to scale up the boiler power to meet the increased hot water requirements.

Try our iHeat boiler size calculator for expert boiler sizing advice in a few easy clicks!

Radiators for New Boilers

When selecting radiators for new boilers, it is vital to understand their role in heating efficiency and the common issues they can face. An informed choice can lead to improved performance of your central heating system.

Why Are Radiators So Important for New Boilers?

Radiators are the primary heat emitters in a central heating system. They facilitate the transfer of heat from the hot water produced by the boiler into the rooms of a home. The efficiency of radiators directly impacts the overall efficiency of the boiler and the central heating system. 

Proper installation by certified engineers ensures maximum effectiveness, often reducing gas bills significantly. Furthermore, incorporating features such as thermostatic radiator valves (TRVs) can enhance the control over individual room temperatures, contributing to energy-efficient heating and cost savings.

Common Radiator Issues

Common issues with radiators include corrosion, sludge build-up, and leaks. Corrosion can occur internally when oxygen reacts with metal, leading to radiator damage and reduced efficiency. 

Sludge is a by-product of internal corrosion and can impair water flow and heat distribution, causing cold spots or complete failure in severe cases. Experienced heating engineers may recommend a powerflush of the pipework and radiators to remove sludge.

System filters can help to protect against future build-up. Regular maintenance and addressing early signs such as noisy operation or leaks can prevent these issues from escalating.

Bleeding/Balancing Your Radiators

Bleeding radiators is necessary when they have cold spots at the top, indicating air trapped inside. This air can hinder water circulation, thereby reducing heating efficiency. Balancing, on the other hand, involves adjusting the valves to ensure an even distribution of hot water to all radiators.

This process may require a heating engineer's experience to guarantee that the central heating system functions optimally. Engineers carrying out a boiler replacement or installation will often bleed and balance the radiators as part of their service.

How Much Do New Radiators Cost?

The cost of new radiators can vary widely based on size, model, and brand. Typically, basic models start from around £50, with premium models or those with a higher heat output reaching several hundred pounds. For example:

Radiator size 

Average Cost (guide only)


£50 - £150


  £100 - £250


£150 - £400

The overall cost involves not only the price of the radiators but also parts, labour, and any additional services like system filter installation. Labour costs in the UK can differ, so obtaining a quote before committing is prudent.

Many firms offer interest-free credit or payment plans to assist with budgeting for home improvements. A comprehensive quote should provide a clear breakdown of these costs.

The Importance of Gas Safe Engineers

When considering a new boiler installation, the competency of the engineer is paramount. In the UK, Gas Safe registered engineers are the only individuals legally allowed to work on gas appliances. This registry is not just a list; it's a guarantee of safety and technical proficiency.

Here at iHeat, ALL of our engineers are Gas Safe registered and can install your new boiler safely and swiftly!

Gas Safe engineers have undergone rigorous scrutiny, proving their qualifications through assessment. They must demonstrate a thorough understanding of gas safety measures and current regulations.

The Gas Safety (Installation and Use) Regulations 1998 lay the groundwork for these standards, ensuring each engineer upholds the highest level of safe practice.

Engaging a Gas Safe engineer is not just about compliance. It's about peace of mind. Unqualified work not only carries legal repercussions but also poses serious risks:

  • Safety Hazards: Gas leaks or incorrect installations can lead to carbon monoxide poisoning, fires, or explosions.

  • Economic Costs: Rectifying botched jobs can be more expensive than investing in a qualified engineer from the outset.

  • Insurance Implications: Unauthorised gas work could invalidate your home insurance policy.

  • Efficiency and Performance: A skilled engineer guarantees an optimally functioning boiler, which is crucial given the rising energy costs. For instance, failing to install a boiler correctly could decrease its efficiency, leading to higher fuel expenses.

Every Gas Safe engineer carries an ID card that delineates their qualifications. Homeowners should check this diligently.

gas safety identification card

What if I Can't Afford a New Boiler?

For homeowners and tenants facing financial hurdles, the prospect of installing a new boiler might seem daunting. 

However, various finance options and government schemes are specifically designed to make boiler replacement affordable for low-income households, ensuring that warmth and efficiency are not exclusive privileges.

New Boilers on Finance

Boilers on Finance offer a practical solution for those unable to pay the upfront costs. Many companies provide finance options, allowing customers to spread the cost over manageable monthly payments. With agreements often ranging from 3 to 10 years, the financial burden is significantly lessened.

  • Monthly Payments: Tailored to suit individual affordability

  • Credit Checks: Typically required to ensure eligibility

iHeat New Boiler Finance

Boiler finance is available with iHeat, below is an example of how the prices work (guide only).


Interest rate (%)




Price (£)

Interest payable (£)

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Government New Boiler Schemes 2024

Here’s an overview of each energy efficiency scheme mentioned, including their main goals and how they function:

Affordable Warmth Obligation 2024


This scheme is a part of the broader Energy Company Obligation (ECO4), focusing on increasing home energy efficiency and reducing fuel poverty among underprivileged households in the UK. It particularly supports the installation of energy-efficient and low-carbon heating systems.


To help vulnerable households by improving heating efficiency, thereby reducing overall energy costs and enhancing living conditions.

Energy Companies Obligation (ECO) 2024


ECO4 is the fourth phase of a government initiative that partners with the UK's largest energy suppliers to improve the energy efficiency of homes, particularly targeting those in need. It supports a wide range of improvements, including boiler upgrades and insulation.


To reduce energy bills and carbon emissions across eligible households, improving energy efficiency through structural upgrades and new technology installations.

LA Flex Scheme 2024


This scheme allows local authorities more flexibility to identify and assist households that may not typically meet the national eligibility criteria for energy efficiency improvements under ECO4. It empowers local councils to address specific local needs.


To extend the reach of government energy efficiency initiatives by including households that might otherwise be excluded due to rigid eligibility criteria, thus broadening the impact on fuel poverty.

Boiler Upgrade Scheme (BUS) 2024


This initiative offers financial support to homeowners and landlords to replace old, inefficient fossil fuel heating systems with newer, greener technologies like heat pumps and biomass boilers.


To encourage the adoption of low-carbon heating technologies, reducing the environmental impact of home heating and contributing to the UK’s broader carbon reduction targets.

Each of these schemes is designed to support different aspects of energy efficiency and fuel poverty, from direct upgrades of heating systems to broader structural improvements, enhancing both individual homes and wider community resilience against energy inefficiency and high utility costs.

New Boiler Extras - Boost Boiler Performance

New boiler extras are optional upgrades that can not only enhance your boilers performance, but can also significantly contribute to reducing heating bills in the long term, below is a list of the most useful boiler extras available at iHeat:

Upgradable Extra

iHeat cost 

Hive Mini, Limescale Reducer & CO Alarm Bundle


Hive Mini Smart Thermostat


Nest Thermostat & Stand


Limescale Reducer


AdvanceFlush System Cleanse


Thermostatic Radiator Valve


CO Alarm


Re-connect Existing Smart Controls


Hive mini smart thermostat

The Hive mini smart thermostat is an innovative smart heating solution designed to provide users with optimal comfort and energy efficiency in their homes.These devices enable homeowners to effortlessly control their heating systems via an intuitive app and smart home integrations.

One of the key features of Hive thermostats is their wireless connectivity, allowing users to adjust temperature settings and heating schedules remotely.

Nest Thermostat & Stand

The google nest thermostat is one of the most cutting edge smart thermostats available due to its ease of use and advanced technology.Nicknamed ‘The Planet Protector’ by its creators, the Google Nest gen 3 Learning thermostat is filled with smart, eco-friendly features as well as being versatile in aesthetics to complement rather than detract from a home. 

Available in 4 colour ways to best adapt to its new surroundings, the Nest Gen 3 is a sleek and contemporary design.

Limescale Reducer

A limescale reducer or inhibitor is a chemical treatment that is added to the water system to reduce the buildup of limescale. It works by forming a thin layer on the inside of the pipes, preventing the minerals from depositing and forming limescale. This treatment is commonly used in areas where hard water is present, such as the UK, to prevent limescale buildup in boilers, pipes, and other appliances.

AdvanceFlush System Cleanse

The ADEY MagnaCleanse complete solution kit can flush through your heating system, being able to remove black iron oxide sludge from your central heating system pipes. It even shifts hardened debris!For the ultimate cleanse, the ADEY MagnaCleanse complete solution kit provides you with a rapidflush filter 1 x, vibraclean agitator combination.

When using the rapidflush filter and vibraclean agitator MagnaCleanse system, flushing removes system debris, and even shifts hardened debris, reducing sludge and blockages and improving heating performance.The benefits of using Adey MagnaCleanse to your central heating system are vast, eliminating debris, reducing the need to bleed your radiators, and reducing the amount of energy needed to heat your home.

On average, you may save up to 6% per year on your energy bills when your central heating system is functioning fully.

This percentage additionally impacts the carbon footprint of your household, providing around 200 - 300 kg fewer emissions across each year.

CO Alarm

A CO (Carbon Monoxide) alarm is one of the most important things installed in a home, as the name suggests, a CO alarm detect any leakage of very dangerous carbon monoxide, and alerts the property occupants.

Carbon monoxide safety is extremely serious and a working alarm can help boost safety levels massively due to the fact the dangerous gas can be hard to detect from sense alone.
If you have a carbon monoxide detector and hear the alarm going off, or notice dark spots on the old style detectors, this means carbon monoxide is present in your home.

If you notice any of the signs above and think you may have a Carbon Monoxide leak, you should call the Gas Safe Register on 0800 408 5500.

Are iHeat Reliable?

is iheat reliable

iHeat have rapidly become one of the heating industry's leading lights, revolutionising the way people buy boilers and putting the customer first.

Due to their efficiency, expertise and ease of use, iHeat are one of the most reliable and celebrated names in UK heating, as evidenced by over 7,000 five-star reviews on Trustpilot to date.

Another hallmark of iHeat's passion and performance is their Which? trusted trader accreditation, the gold standard in new boiler installation.

Thousands of happy customers

Pushing customer service excellence to new standards, ensuring every customer has a 5 star service.

New Boiler Cost - Conclusion

Investing in a new boiler is generally considered a wise decision for homeowners, particularly when considering the array of benefits offered by modern, energy-efficient models.

New boilers bring enhanced efficiency, which directly translates to reduced energy consumption and lower heating bills.

This not only saves money over time but also aligns with broader environmental goals due to decreased carbon emissions.

Additionally, the latest boiler technologies ensure increased reliability and reduced likelihood of breakdowns, providing peace of mind during colder months.

The improvement in home heating quality contributes to a more comfortable and consistently warm living environment.

Modern boilers can also boost property value, making homes more attractive to potential buyers should you decide to sell in the future.

Furthermore, new boilers typically come with long-term warranties that protect against unforeseen issues, ensuring further security and peace of mind.

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Frequently Asked Questions

How Much Does It Cost to Replace a Boiler in the UK?

The cost of replacing a boiler in the UK can vary significantly depending on the type of boiler, the complexity of the installation, and your location. On average, homeowners can expect to pay between £1,500 and £4,500. This price range includes the cost of the new boiler and professional installation fees. For high-end models or more complex installations, costs can rise to around £5,000. It's important to get multiple quotes to find the best price and service.

What is the Life Expectancy of a New Boiler?

The typical life expectancy of a new boiler is around 15 to 20 years. However, this can vary based on the brand, model, and how well the boiler is maintained. Regular servicing and timely repairs are crucial to maximizing the lifespan of your boiler.

How Often Should You Replace a Boiler?

Boilers should be replaced approximately every 15 to 20 years. However, this timeframe can vary depending on the boiler’s performance and maintenance. If your boiler is frequently breaking down, experiencing efficiency issues, or parts are becoming hard to source, it might be time to consider replacement sooner.

Is It Worth Replacing a 20 Year Old Boiler?

Yes, replacing a 20-year-old boiler is generally worth it. Older boilers often operate at significantly lower efficiency levels compared to newer models, leading to higher energy bills. Modern boilers are more energy-efficient, environmentally friendly, and include advanced features that enhance heating control and comfort.

Is It Worth Repairing a 20 Year Old Boiler?

Repairing a 20-year-old boiler can be cost-effective if the repairs are minor. However, for more significant issues, replacement is often a better choice economically. Older boilers also tend to be less energy-efficient, so investing in a new boiler can save money on energy bills in the long run.

Is Replacing a Boiler a Big Job?

Replacing a boiler can be a big job, particularly if you are changing the type of system or if it involves extensive pipework modifications. The process typically involves removing the old boiler, fitting the new one, and possibly upgrading components like thermostats and radiators. Hiring a qualified professional is essential to ensure the job is done safely and efficiently.

Can a Boiler Last 30 Years?

While it’s possible for a boiler to last 30 years, especially with meticulous maintenance, it is quite rare. Most boilers will experience a decline in efficiency and more frequent breakdowns as they age beyond their typical lifespan of 15 to 20 years. Upgrading to a new boiler can provide improved reliability, efficiency, and safety.

Stephen Day profile photo
Article by
Stephen Day | Co-founder
Gas Safe registered and FGAS certified engineer with over 20 years experience in the heating and cooling industry.