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Updated: April 11, 2024

Finding the right boiler for your home can be overwhelming, but Let’s Heat is here to simplify the process for you. Our comprehensive guide will walk you through everything you need to know to make an informed decision when it comes to boiler installation.

A boiler is a vital component of any modern household, providing hot water for both your taps and heating system. Shopping for a new boiler can often feel daunting and costly, but Let’s Heat streamlines the process by offering a convenient online guide to help you navigate your options.

We’ve condensed the essential factors you need to consider to ensure you purchase the perfect boiler for your requirements. Trust Let’s Heat to provide you with the guidance you need for a hassle-free boiler installation experience.

What is the cost for a new boiler replacement?

The first thing you might think of when buying a new boiler is the possible cost. Boilers can be expensive but getting a good boiler is a good investment.

You will of course want your boiler to be efficient and to last for years to come.

The price for a new boiler replacement can vary, depending on many crucial elements:

  • The type of boiler you want to install in your house (e.g. combi, system or regular)
  • Moving you boiler to a different location
  • The model you aim to buy (e.g. mid-range vs. premium)
  • Converting your current boiler with another type (e.g. system to combi)
  • The extras you get (e.g. filters, a controller or smart thermostats)

Undoubtedly, opting to replace your existing combi boiler with a new one is a more cost-effective solution compared to converting your system boiler to a combi boiler.

Converting your boiler entails additional expenses in terms of time, labor, and materials, not to mention the complexity of the entire process.

The choice of boiler model also significantly impacts the overall cost of the installation. At Let’s Heat, we proudly offer some of the top brands in the boiler industry, including Alpha, Worcester Bosch, and Viessmann.

Moreover, Let’s Heat provides flexible payment options to suit your needs. Whether you prefer to pay upfront in cash or opt for a boiler finance plan allowing you to spread the cost over monthly installments, we’ve got you covered. Trust Let’s Heat to make your boiler installation experience convenient and affordable.

Read about: Affordable Boiler Prices

The Best Brands of System Boilers & Pricing

What boiler brand to choose? 

To kick off the process, selecting a reputable boiler brand is paramount. A quick glance at the accolades they’ve earned can be telling of their reliability. For instance, Worcester Bosch has clinched the Which? Best Buy award for the past decade, underscoring their longevity and dependability.

Opting for a brand with a solid track record ensures they’ll be around for the long haul to honor your boiler warranty. A lengthy warranty, such as a ten-year term, signals the manufacturer’s confidence in their product’s durability, provided it’s maintained regularly.

Prioritizing a boiler that boasts longevity minimizes the likelihood of breakdowns in the foreseeable future. While the initial investment may be higher, the potential savings on repair costs over time make it a prudent choice.

Read about: The Best Brands of System Boilers & Pricing

Some important factors to consider for a boiler replacement:

As has been noted, a new boiler replacement might not be that cheap. So it’s important to consider some key factors before making your final decision.

The size of boiler you need (kW output)

When discussing boiler size, we’re referring to its power output, measured in kilowatts (kW), rather than its physical dimensions.

It’s important to note that a higher output rating indicates a more powerful boiler. However, opting for the highest output isn’t always the best choice. Oversizing your boiler can lead to increased energy bills, while undersizing may fail to meet your heating demands effectively.

To determine the appropriate output rating for your home, consider factors such as the number of bathrooms and radiators. This information provides insight into your domestic hot water and central heating requirements.

For personalized advice, it’s advisable to request a quote from a Gas Safe registered engineer. Additionally, many manufacturers offer guidance on their websites to help you select the right boiler for your needs. Consulting manufacturer guidelines can further assist you in making an informed decision.

No. of bedrooms1 bath & shower2 baths & showers
2-bedroom house26kW29kW
3 -bedroom house29kW35kW
4-bedroom house29kW35kW
5-bedroom house35kW35kW

In small homes with limited space and only one bathroom, a combi boiler is often the most suitable option.

Consideration of the new boiler’s location is crucial. Installing the new boiler in the same location as the old one can streamline the process and reduce costs. However, relocating the boiler to a different spot will incur additional expenses due to the need for extra work and materials, such as installing a new flue and rerouting pipework.

Prioritizing energy efficiency is key to reducing carbon footprint and heating costs. Let’s Heat offers modern A-rated boilers paired with smart thermostats to minimize energy wastage and maximize savings.

According to the Energy Saving Trust, replacing an old boiler with an A-rated model and heating controls can save approximately £340 and 1,500kg of carbon dioxide annually.

Installation time varies depending on the complexity of the job. While replacing a combi boiler with another combi boiler may take around 1 day, converting a combi boiler to a system boiler could require up to 2 days due to the intricacy of the process. Trust Let’s Heat to ensure efficient and hassle-free boiler installation tailored to your needs.

Emergency Boiler Repair

When should you replace your boiler?

Boilers typically have a lifespan of around 10 years, so if your boiler has reached this age, it’s a clear indication that it’s time for a replacement.

Moreover, there are several other compelling reasons to consider investing in a new boiler:

Old and Inefficient: Boilers over 10 years old typically have a low efficiency rating (G-rated), wasting a significant portion of energy. Modern boilers, with efficiency ratings of around 90%, offer substantial energy savings.

Costly Repairs: Older boilers can become increasingly expensive to repair, especially if major components such as the PCB or heat exchanger need replacement. In such cases, investing in a new boiler may prove more cost-effective in the long run.

Relocation: If you’re planning to relocate your boiler to a different spot in your home, installing a new boiler with a fresh warranty is a sensible choice.

Inadequate Hot Water: If your current boiler struggles to meet your household’s hot water demands, it may be time to upgrade to a model with a higher power output.

    With these considerations in mind, replacing your boiler with a newer, more efficient model can lead to enhanced performance, energy savings, and peace of mind. Trust Let’s Heat to assist you in finding the perfect boiler replacement tailored to your needs.

    If you’re getting a new boiler, then you should know that there are three major types:

    Combi boilers

    When considering a new boiler, it’s essential to understand the three main types available:

    Combi Boilers: Combi boilers have surged in popularity in recent years, particularly for average-sized homes. But what exactly are they and how do they function? The term “combi” stands for combination boiler, indicating that

    these units provide both hot water and heating. This all-in-one design eliminates the need for separate immersion heaters and water tanks, streamlining the system. Unlike older setups where hot water wasn’t always readilavailable,

    combi boilers offer on-demand hot water, reducing wait times and operational costs. Additionally, their compact size makes them ideal for homes with limited space.

      In summary, if you’re in the market for a new boiler and live in an average-sized home, a combi boiler offers convenience, efficiency, and space-saving benefits. Trust Let’s Heat to assist you in selecting the perfect boiler to meet your needs.

      Why are combi boilers so popular?

      As has been noted, Combi boilers have two functions (providing hot water and heating). As a result, they are very efficient . Green Combi boilers are up to 98% more efficient. Their compact shape and design makes them perfect for homes with limited space. They can also be installed in kitchen cupboards.

      How do Combi Boilers work?

      In a combi boiler system, cold water is supplied directly from the main water source, while gas fuel is burned to produce heat. This heat is then transferred to the water through a heat exchanger in the combustion chamber.

      Your thermostat monitors the temperature in your home and signals the combi boiler to activate when temperatures drop. Once the desired heat level is reached, the boiler adjusts its output to maintain a consistent temperature, reducing energy waste and keeping your home comfortable.

      Combi boilers prioritize hot water delivery to whichever outlet is in use, whether it’s a hot tap, shower, or bath. When the tap is turned off, the boiler resumes its central heating duties.

      It’s important to note that while a combi boiler can deliver hot water to outlets and central heating, it cannot do both simultaneously. Trust Let’s Heat to provide expert guidance on selecting and installing the right combi boiler for your home.

      What are the advantages of Combi Boiler?

      High Efficiency:

      Combi boilers are highly efficient in energy consumption, resulting in significant cost savings. By providing both hot water and heating from a single unit, they optimize energy usage.

      Compact Size:

      Ideal for small homes, combi boilers eliminate the need for additional space for water tanks or cylinders. They draw water directly from the mains, saving valuable space.

      Instant Hot Water:

      With a combi boiler, there’s no need to wait for hot water to be heated and stored. Hot water is available on demand, ensuring convenience and comfort.

      Installation Flexibility:

      Combi boilers, being compact and single-unit systems, offer flexibility in installation. They can be installed in various locations within a property, providing versatility in placement options. Trust Let’s Heat to expertly install your combi boiler for optimal efficiency and performance.

      Best combi boilers & boiler brands

        What are the disadvantages of Combi Boilers?

        It’s worth mentioning that their advantages outweigh the disadvantages.

        1. The Flow Rate is Limited

        Using two or more taps at the same time will reduce the water flow rate. For one thing, a combi boiler is not recommended for those who live in larger homes or those who have multiple bathrooms.

        3. Relying on water pressure from the mains

        A combi boiler heats the water coming from the mains. It won’t work adequately if your water pressure is low.

        In conclusion:

        • Perfect for homes with limited space
        • A hot water storage cylinder and a cold water tank are not needed
        • Unsuitable for larger homes with many bathrooms or a high demand for hot water
        • Inadequate for places with low water pressure

        Regular (heat only) boilers

        What is a Regular (Conventional) Boiler?

        A regular boiler, also known as a heat only or conventional boiler, is a traditional heating system commonly found in homes across the UK. It comprises a large water tank typically located in the loft and a hot water cylinder situated in an airing cupboard. If your home features these components, it likely has a regular boiler.

        How do Regular Boilers Work?

        Regular boilers operate straightforwardly. They draw water from the tank to provide heating throughout the home. Optimal performance is achieved by placing the tank as high as possible to facilitate efficient water flow within the system.

        When a hot tap is opened or the heating is activated, a heat exchanger within the boiler warms the cold water. The heated water then flows into the hot water storage cylinder, where it is stored and circulated as needed. Valves

        within the system direct hot water to either the central heating system or the taps and outlets as required. Trust Let’s Heat to expertly install and maintain your regular boiler for reliable heating performance.

        What are the advantages of regular boilers?

        Advantages of Regular Boilers:

        Simple Replacement Process:

        Upgrading from an old regular boiler to a newer model is a straightforward and cost-effective process, minimizing disruption and potential damage to your home.

        High Demand Heating and Hot Water:

        Regular boilers are well-suited for homes with multiple bathrooms, efficiently meeting high demands for hot water and heating. Their large hot water storage capacity allows for simultaneous use of multiple taps and outlets.

        Increased Efficiency:

        Modern regular boilers, especially those equipped with condensing technology, offer high levels of efficiency, reducing energy consumption and lowering heating bills. Some models boast efficiency ratings as high as 97%.

        Immersion Heater Backup:

        Regular boilers can be fitted with an immersion heater as a backup system, ensuring continuous access to hot water in the event of a boiler breakdown. This provides peace of mind and convenience for homeowners.

        Solar Compatibility:

        Regular boilers are compatible with solar thermal panels, allowing homeowners to harness solar power to produce hot water. This eco-friendly option can further reduce energy costs and environmental impact. Ensure compatibility

        between your chosen boiler model and solar thermal systems before installation. Trust Let’s Heat to guide you in selecting and installing the ideal regular boiler for your home’s heating needs.

          What are the disadvantages of regular boilers?

          Delayed Hot Water Availability:

          During peak usage times or after exhausting the stored hot water in the cylinder, there can be a delay before hot water is available again. This inconvenience may require homeowners to plan their hot water usage accordingly.

          Space Requirements:

          Regular boilers necessitate space for both the water tank and hot water cylinder, making them less suitable for smaller homes or properties with limited space. The additional space required may pose challenges for installation and storage.

          Costly Installation:

          The installation of a regular boiler can be more complex and costly compared to other types of boilers. Due to the numerous components involved and potential need for additional pipework and space considerations, the installation

          process may incur higher expenses and longer completion times. Trust Let’s Heat to provide expert guidance and efficient installation services for your regular boiler needs.

            In conclusion:

            • Good for homes with multiple bathrooms and a high hot water demand
            • Perfect for areas with low water pressure from the mains
            • Suitable for homes with older heating systems that may not be able to tolerate high pressure
            • They take space since they need a cistern tank
            • A tank in the attic can freeze in winter and might cause many problems if it starts leaking
            guide to boiler installation

            What is a system boiler?

            A system boiler, also known as a sealed system boiler, is a type of central heating boiler that works alongside a hot water storage cylinder. Unlike combi boilers, which heat water on demand directly from the mains, system boilers heat water in a central heating system and store it in a cylinder for later use.

            how a system boiler typically works

            1. Heating Process: The boiler heats water in a central heating system, usually using gas, oil, or electricity as the fuel source. The heated water is circulated through radiators or underfloor heating systems to provide warmth throughout the home.
            2. Hot Water Storage: In addition to heating the central heating system, a system boiler also heats water for domestic hot water usage. The heated water is stored in a hot water cylinder, which is often located in an airing cupboard or another designated area within the home.
            3. Controlled Delivery: When hot water is needed for taps, showers, or baths, it is drawn from the hot water cylinder. The system boiler ensures a steady supply of hot water is available for domestic use, even during periods of high demand.
            4. Sealed System: System boilers operate on a sealed system, meaning that the water used for heating and hot water is contained within a closed loop. This helps to maintain water pressure and efficiency within the system.

            What are the advantages of system boilers?

            Advantages of System Boilers:

            Ample Hot Water Supply: System boilers can store large quantities of hot water, making them suitable for homes with multiple taps, showers, and radiators in use simultaneously.

            Solar Energy Integration: By connecting the appropriate cylinder to the system, you can harness solar energy, reducing environmental impact and lowering utility bills.

            Space Efficiency: Compared to regular boilers, system boilers require less space and do not necessitate an expansion tank or external vessels, simplifying installation.

            Economic and Efficient: System boilers feature a built-in pump for fast response times and more economical operation, helping to reduce running costs over time.

              Disadvantages of System Boilers:

              Space Requirement: While smaller than regular boilers, system boilers still require more space than combi boilers due to the need for an external cylinder, posing challenges for installation in smaller homes.

              Limited Capacity During Peak Usage: Despite adequate cylinder sizing for typical household needs, high-demand periods with increased hot water usage may deplete the stored supply, requiring time for reheating and resulting in temporary inconvenience.

                In conclusion:

                • Also recommend for homes with more than one bathroom and a high demand for hot water
                • Do not need a tank in the attic
                • Internal components can make installation much easier.
                • Unsuitable for areas with low water pressure
                • Not suitable for homes with traditional heating systems that can’t tolerate high water pressure
                • You need to consider where to put the water tank if a system boiler is replacing your combi boiler.

                Read about: Electric Boilers v Gas Boilers

                What is meant by a Condensing Boiler?

                Condensing boilers are a standard requirement for new boiler installations, mandated by law. They feature a larger heat exchanger compared to non-condensing models, enabling them to extract additional heat from fuel. This results in significantly higher efficiency levels.

                Unlike non-condensing boilers, which lose a substantial amount of heat in exhaust gases, condensing boilers capture and utilize this heat to warm water. As a result, they can operate at efficiency levels of up to 90%, leading to reduced heating bills and environmental benefits.

                If you’re experiencing issues with your current boiler, Let’s Heat can assist in diagnosing the problem and determining whether a replacement is necessary. Our dedicated staff and skilled engineers are available to provide expert guidance and assistance, ensuring your heating needs are met efficiently and effectively, regardless of the time or day.

                Over the last few years, the UK has passed some guidelines for boiler installation and energy efficiency:

                • Gas boilers should have at least a 92% ErP efficiency regardless of boiler type.
                • A Combi boiler installation should have one energy-saving feature.
                • You should have functioning time and temperature controls.

                Read more:

                New Boiler Quote

                New Boiler Cost

                Boiler Installation in Aberdeen

                Which boiler brand to choose from?

                We offer a variety of different boilers from different brands. You can take a look at some of the types we offer down below:

                Viessmann Boilers

                Viessmann boilers have won plenty of awards. They have a reputation for being technically superb.

                With its superb German engineering and simple, crisp designs, it has a 5-star reputation. Needless to say that it dominates the European boiler market.

                Worcester Bosch Boilers

                When it comes to boilers, then rest assured that Worcester Bosch is a household name. It is an award-winning boiler.

                It is the best boiler brand in the UK thanks to their excellent guarantee offer, customer service, and easily sourced parts.

                Alpha Boilers

                Over the last few years, Alpha has increased its share of the market due to it being a budget-option for many customers.

                It is a fantastic option for people who are looking for a reliable yet affordable boiler.

                Finance option

                If you find yourself unable to buy a new boiler outright, then you should consider a boiler finance plan.

                If you are eligible to use boiler financing, then you will be able to pay monthly for your boiler over the course of 2, 4, 6 or 10 years.

                To sum up:

                • No deposit is needed
                • You can make overpayments with no penalty
                • The ability to spread the cost over 2, 4, 6, or 10 years
                • Interest rates from 9.9% APR

                Does boiler financing cover the cost of installation?

                Of course, it does. The cost of the installation can be included in your monthly plan. In other words, you don’t have to worry about financing the installation cost. We will remove your old boiler, get you a new one and install it. And all the installation fees will be part of your monthly payment plan.

                Read about: Best combi boilers & boiler brands

                How does Interest-free boiler finance (0% APR) work?

                You can benefit from 0% interest-free boiler financing with flexible payment terms, typically offered by many boiler companies and financing providers. With this option, you can spread the cost of your boiler over a convenient 12-month period without incurring any interest charges.

                Here’s how it works: the boiler company subsidizes the financing provider, allowing you to enjoy interest-free payments. This means that the total cost of your boiler remains fixed, with no additional fees or charges beyond the agreed-upon monthly payments and installation costs.

                For more information on our interest-free financing plan, don’t hesitate to get in touch with us. We’re here to assist you every step of the way.

                Getting the perfect repayment plan 

                You can talk to our financial advisor who will guide you on what repayment plans are available if you want to. If you choose to go with an interest-free plan or a flexible payment plan, there are many options to choose from.

                What is next-day boiler installation?

                Nowadays, next day boiler installation is very popular in the UK. The process is very simple. You can just choose your boiler online or get a quote from us. A date will be arranged for the installation of your boiler by one of our Gas Safe registered engineers.

                Read more about: Boilers On Finance | Pay Monthly Finance In Uk

                What are the steps of next-day boiler installation?

                The process of next-day boiler installation typically involves several key steps, though the exact number may vary depending on the specific requirements of your installation. Here’s a general overview:

                Removal of the old boiler: The first step is to remove the existing boiler and any associated pipework. This may involve disconnecting and dismantling the old unit, as well as removing any redundant pipework and components. Ensuring clear access to the boiler area can help streamline this process.

                Installation of the new boiler: Once the old boiler has been removed, the new boiler and its associated pipework will be installed. This step may vary in duration and complexity depending on factors such as the type of boiler being installed, the location of the installation, and any additional requirements.

                Testing and commissioning: After the new boiler has been installed, it will undergo testing and commissioning to ensure that it is functioning correctly and safely. This may involve checking for leaks, verifying pressure levels, and calibrating the boiler controls. The heating engineer will also conduct a thorough inspection to confirm that the installation meets regulatory standards.

                Product demonstration: Once the installation and testing are complete, the heating engineer will provide a demonstration of the new boiler. This will include instructions on how to operate the controls, set heating schedules, and troubleshoot common issues. Taking notes during this demonstration can be helpful for future reference.

                Final checks and documentation: Before completing the installation, the heating engineer will perform a final inspection to confirm that everything is in order. They will also provide any necessary documentation, such as warranty details and service records, and address any remaining questions or concerns you may have.

                  By following these steps, a next-day boiler installation can be completed efficiently and effectively, ensuring that you have a reliable heating system in place as quickly as possible.

                  Read more about: Worcester Bosch Greenstar 8000 Life Combi Boiler Review 

                  Combi boilers common faults  

                  Glow-Worm Boiler Error Codes / Fault Codes

                  Should I repair my boiler or get a new boiler installed?

                  There is no easy answer to this question since it depends on a number of factors, such as the age and condition of your boiler, the cost of repairs, and the cost of a new boiler installation. However, as a general rule, if your boiler is more than 15 years old or if it has begun to break down frequently, it is probably time to start thinking about replacing it.

                  Does a Gas Safe registered installer have to fit the boiler?

                  Yes, a Gas Safe registered installer must fit the boiler in order to ensure that it is installed correctly and safely. This will help to avoid any potential issues with the boiler, such as gas leaks or fires.

                  Why buy a new boiler?

                  There are many reasons to purchase a new boiler. Perhaps your old one is outdated and inefficient, or it may no longer be able to meet your needs. A new boiler can provide increased performance and energy savings, as well as peace of mind knowing that you have a reliable system.

                  What size boiler do I need?

                  There is no one-size-fits-all answer to this question, as the size of boiler you need will depend on a number of factors, including the size of your home, the number of people living in it, and your hot water needs. However, a qualified heating engineer should be able to help you choose the right size boiler for your home.

                  Can I move my boiler to a new location?

                  It is possible to move your boiler to a new location, but it is best to consult with a professional first to ensure that the new location is suitable. They will be able to advise you on any potential problems that could arise from moving the boiler, such as ventilation or structural issues.

                  Why does boiler efficiency matter?

                  Boiler efficiency matters because it determines how much fuel your boiler consumes. The more efficient your boiler is, the less fuel it will consume and the lower your energy bills will be.

                  How long does it take to install a regular boiler?

                  A regular boiler can take between 1 to 3 days. The complexity of the installation will determine the duration. A like-for-like boiler replacement would be the quickest to do. However, replacing a different kind of boiler would take longer time to finish. For instance, a combi boiler replaced with a regular boiler will require installing a hot water cylinder, a tank and re-routing the pipework. Lastly, moving your boiler would also increase the installation time.

                  How long does it take to install a system boiler?

                  A system boiler can take between 1 to 3 days. The complexity of the installation will determine the duration. A like-for-like boiler replacement would be the quickest to do. However, replacing a different kind of boiler would take longer time to finish. For instance, a combi boiler replaced with a system boiler will require installing a hot water cylinder and re-routing the pipework. Lastly, moving your boiler would also increase the installation time.

                  What happens during a boiler installation?

                  During a boiler installation, the technician will first disconnect the power to the boiler. They will then remove the old boiler and any associated pipes or wiring. The new boiler will be installed in the same location as the old one, and new pipes or wiring will be run to connect it to the existing system. The technician will then test the new boiler to ensure it is working properly.