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  • Step by step guide to boiler installation

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    • Step by step guide to boiler installation

    Updated: February 29, 2024

    Getting a new boiler might be a tedious task. But don’t worry. smartadapt can help make this an easy process. We have prepared a complete guide to help you get the right boiler for your home. So if you are looking for boiler installation, you have come to the right place.

    A boiler is one of the most important things in any modern home. It supplies your outlets and your heating system with hot water. We know how tiring it is to go shopping for a new boiler. The process can be complicated and expensive. However, with Let’s Heat, you can just check what you need to know online following this guide.

    We will try to sum up the most important factors you need to know in order to buy what you exactly need.

    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)

    Without a doubt, replacing your current combi boiler with another is cheaper than converting your system boiler to a combi boiler.

    Converting your boiler requires more time, more labour and more materials. Not to mention how complex the whole process is.

    Which model you pick also plays a huge role in determining the cost for a new boiler. Here at Let’s Heat, we offer some of the best brands in the boiler industry such as Alpha, Worcester Bosch and Viessmann.

    With Let’s Heat you can choose from the multiple ways of payment we offer to our customers. You can pay in cash or get a boiler finance plan that will enable you to pay monthly for your new boiler.

    Read about: Affordable Boiler Prices

    Boiler Installation
    Step By Step Guide To Boiler Installation 7

    What boiler brand to choose? 

    To begin with, you would want to start the process by choosing a boiler brand that is trustworthy. In order to identify a good boiler brand, you can just check how many awards they have won. Worcester Bosch, for the last ten years, have won the which? Best Buy award. This shows that they have been in business for a long time and that they are quite reliable. 

    You would want a company that lasts long in order to guarantee that they will be there in the long run to honour your boiler warranty. When you are offered a long warranty, say for ten years, then it means that the company has trust in its product and knows that it can last that long without breaking down, given that it is serviced regularly. 

    It is advisable to choose a boiler that will not easily break down in the foreseeable future. You might initially pay more but you will save on the repair cost in the long run.

    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 we talk about boiler size, we do not mean its dimensions, but rather its power output. The unit of measurement, used for boilers, is the kilowatt (kW).

    To clarify, the higher the output of your boiler, the more powerful it will be. Nonetheless, it’s never a great idea to get the boiler with the highest output rating. A too high output rating would increase your energy bills. And a too low output rating will not meet your demand.

    Through counting the number of bathrooms and radiators in your home, you can find the most appropriate output rating for you. This information can also help you have an idea of the level of demand for domestic hot water and central heating.

    With this purpose in mind, we advise you to get a quote from a Gas Safe registered engineer. If you have a brand in mind, then you should check their website and guidelines. A lot of manufacturers, nowadays, offer advice on their websites.

     Here is a table to guide you through what you need to know:

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

    To point out, small homes with one bathroom and little or no space for a cylinder should consider getting a combi boiler.

    Location of the new boiler

    It will cost you less if you install your new boiler in the same location as the old. Moreover, it will make the job more straightforward.

    On the other hand, you can move your new boiler to a different location if you want to. But it goes without saying that you will have to pay more.

    The process of moving your boiler requires more work and materials. You will need a new flue installed and new pipework re-routing through your home. This process can be very messy though.

    Energy efficiency

    If you want to reduce your carbon footprint, save some money and keep your house warm and fuzzy, then it’s important to get an energy-efficient boiler.

    At Let’s Heat, we offer modern A-rated boilers that can be bought with a smart thermostat in order to reduce energy wastage.

    You can save about £340 and 1,500kg of carbon dioxide a year if you replace your old boiler with an A-rated boiler and set of heating controls according to the Energy Saving Trust.

    Installation Time

    Some replacement boiler installations take longer than others. Some are just more complicated than others.

    For instance, replacing your combi boiler with another combi boiler might take around 1 day.

    On the other hand, converting, for example, a combi boiler to a system boiler is probably going to take 2 days.

    Boiler Installation
    Step By Step Guide To Boiler Installation 8

    When should you replace your boiler?

    Generally speaking, boilers are estimated to last around a decade (10 years). So if your boiler is that old, it’s a good sign that it’s time to replace it.

    Additionally, there are other reasons as to why you should get a new boiler. These might be:

    Your boiler is old and inefficient

    Boilers that are more than 10 years old are G-rated. They have an efficiency rating of around 70%. As a result, for every £1 you spend, 30p is wholly wasted. Modern boilers, on the other hand, are 90% efficient.

    Your boiler is too expensive to repair

    In some cases, broken boilers are very costly to repair. Especially if you need to replace or repair parts like the PCB or the heat exchanger. In short, it might be more cost-effective for you to get a new boiler instead.

    Moving your boiler

    If you want to change the location of your boiler, then it makes sense to get a new boiler installed with a brand new warranty.

    Your boiler can’t meet hot water demands

    It might be time to replace your boiler with a new model that has a higher power output if your current boiler is unable to meet your hot water demands.

    What are the types of gas boiler replacement?

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

    Combi boilers

    Combi boilers are one of the most popular options for people to install in recent years. If you are living in an average sized home, then combi boilers are your best choice. But what are they and how do they work?

    The word Combi stands for combination boiler. This single unit both provides hot water and heating. That’s why they are better than older systems that consisted of an immersion heater which is supplied with water a tank way up.

    With the older system, hot water wasn’t always on-demand. To have hot water, you need to turn on the water heater in advance. Not to mention the high cost and the amount of money of operating these older systems. Furthermore, an older system is much larger and needs a lot of space.

    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?

    Cold water runs through the combi boiler directly from the main water source. In order to produce heat, the gas fuel  is burned. The heat is then transformed from the combustion chamber to the water through a heat exchanger.

    Your thermostat would know when the temperatures drop in your house. Subsequently, it will send a signal to the combi boiler which would fire up and heat your home.

    The minute the required heat is reached, your combi boiler would decrease the produced heat and keep the status quo. As a result, your energy waste will be reduced  as well as keeping your house warm.

    A Combi boiler directs hot water to any outlet you are using such as a hot tap, a shower or a bath. When you turn off the tap, the central heating duties will be restored.

    Keep in mind that hot your Combi boiler directs hot water to the water outlets or the central heating, but not both at the same time.

    Read about: Best Combi Boilers to Buy (and avoid)

    What are the advantages of Combi Boiler?

    1. A combi boiler is very efficient

    A combi boiler is very efficient when it comes to energy consumption. It would save you a lot of money since it can be used for both providing hot water and heating your home.

    2. They are small in size

    A combi boiler is perfect for a house that is small in size. You will not need to have space for a water tank or cylinder due to the fact that a combi boiler takes water from the mains directly.

    3. On-demand hot water

    With a combi boiler you don’t need to worry about having enough water in the hot water storage. It will provide hot water instantly.

    4. Installation Flexibility

    Combi boilers are relatively small and consist of a single unit. As a result, they can offer more flexibility when it comes to their Installationplace.

    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

     Types Of Gas Boiler Replacement
    Step By Step Guide To Boiler Installation 9

    What is a Regular (Conventional) Boiler?

    A regular boiler is the traditional heating system you can find all across the UK. It is also known as a heat only boiler or a conventional boiler. A regular boiler consists of a big tank of water in the loft and a hot water cylinder in an airing cupboard. If you have these two items in your home, then you have a regular boiler.

    How do regular boilers work?

    It is all pretty simple. Basically, a regular boiler will take water from the tank to provide heating. It is important to place your tank as high as possible to have a better water flow in all the systems.

    A heat exchanger warms up the cold water once you turn on the hot tap or switch on the heating. After that the hot water moves to the hot water storage cylinder where it is kept and circulated. Then valves will direct hot water to the heating system or the taps and outlets.

    What are the advantages of regular boilers?

    Replacement is simple and easy

    Replacing your old regular boiler with a newer version is less costly and damaging to your home. So it’s always the safer option to go with if you don’t want to spend a lot or worry about damages.

    Meets your high demand of heating and hot water

    If you have a home with multiple bathrooms, then a regular boiler is a great choice. It can meet your demand for hot water and heating. With a large capacity to store hot water, it means that you can use several taps and outlets at the same time simultaneously.

    More efficiency

    Older boilers with no condensing technology should be replaced with a condensing boiler. Condensing boilers are more efficient and consume less energy. As a result, they will reduce the cost of your heating bills. Nowadays, some regular boilers are 97% efficient.

    Able to have an immersion heater as a backup

    A backup immersion heater would make sure that you don’t go out without hot water in case your boiler breaks down. The Immersion heater would be fitted in the hot water cylinder.

    Solar compatibility

    At present, you can use solar thermal panels to produce hot water using solar power. Just make sure that your cylinder and model you buy are compatible with solar thermal.

    What are the disadvantages of regular boilers?

    Hot water isn’t always instant in busier times

    Once you use all the stored hot water in your cylinder, you have to wait for some time to be able to use hot water again. Always buy a cylinder with the capacity to meet your hot water demand and needs.

    Needs lots of space

    Regular boilers need space for the water tank and the hot water cylinder. That’s why it’s not a good choice for smaller homes that don’t have much space. For smaller homes, a combi boiler is more suitable.

    Installation can be costly

    Because there are many parts to be installed around the house, a new boiler installation can be pricey. Aside from being expensive it can also take a lot of time.

    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

    System boilers

    What is a system boiler?

    Nowadays, people in the UK are advised to use a combi boiler for their hot water needs. But a system boiler can, sometimes, be a better option for certain situations.

    Let’s take a look at what a system boiler means and see how they work. In addition to looking at some of the main reasons why a system boiler might be your best choice.

    How do system boilers work?

    Firstly, a heat exchanger heats the water. Then it moves energy from the gas jets to the water.  Once the water is heated, it is moved to the hot water cylinder where it will be stored. Even when you are using multiple taps and showers, a constant supply of hot water is always available.

    What are the advantages of system boilers?

    There are many advantages to having a system boiler as your main source of hot water.

    A large supply of hot water

    With a system boiler you can store large quantities of hot water to use later on. This is very useful when you are using multiple taps, showers and radiators at the same time.

    The ability to use solar energy

    Connecting the correct cylinder to the system will enable you to use solar panels. This is not only environmentally friendly but it is also cost-effective and will save you some money.

    Needs less space than a regular boiler

    System boilers are easier to install and need less space than regular boilers. They do not need an expansion tank or external expansion vessels.

    Economical and fast

    System boilers consist of a pump. As a result, they respond fast and have more economic running costs.

    What are the disadvantages of system boilers?

    There are some drawbacks to installing a system boiler that you should keep in mind. Here are a few of them:

    System boilers need more space than combi boilers

    Although they take less space than regular boilers, they still require more space than combi boilers because of the external cylinder. This can be a huge problem in smaller homes when it comes to installations.

    Busier times means more patience

    Your cylinder will be sized in advance to cover your household need of water (usually 50 litres of hot water stored per person). However, in times when you have more visitors than usual and your use of hot water is doubled, your hot water storage may run dry. As a result, you will have to wait 30-40 minutes while your boiler is reheating the cylinder again.

    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 A System Boiler?
    Step By Step Guide To Boiler Installation 10

    What is meant by a Condensing Boiler?

    The terms condensing and non-condensing can be confusing to people shopping for a new boiler. Presently, it is stated by law that new boilers must use condensing technology. In short, you don’t have to worry about getting a condensing boiler.

    Condensing is not a type of boiler, but rather a technical feature. In a Condensing boiler you get a much bigger heat exchanger. They also produce additional heat from the fuel. The same fuel that would have been wasted in a non- Condensing boiler. As a result, they are more efficient.

    non-condensing boilers are less efficient by 50% since a lot of heat was lost in the combustion exhaust gases. On the other hand, new boilers would capture this heat and use it to heat water.

    condensing boilers are energy efficient by 90%. They use excess energy to heat your property. Not to mention, they are environmentally friendly and reduce your heating bill.

    Identifying the problem!

    If you are having issues with your current boiler, then you can have it fixed or replaced. We can help you diagnose the problem and determine whether you actually require a new boiler or not. We have excellent staff here at Let’s Heat. Our engineers can help you with what you need and are available regardless of the time and day.

    Energy regulations

    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

    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 easily get 0% interest-free boilers with payment terms of 12 months from most boiler companies and boiler financing providers.

    Boiler finance provided by a bank or a lender will ensure that you won’t pay a penny of interest over a set term. Here is how it works. The boiler company pays a subsidy to the bank. And that’s how they are able to make their money.

    In short, the price of your boiler wouldn’t increase because of interest, and there are no additional charges or fees. So you will only pay the agreed-upon monthly payments and the installation cost without extra fees.

    If you want to know more about our free-interest plan, feel free to contact us.

    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.

    Next day boiler installation

    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

    Boiler Finance
    Step By Step Guide To Boiler Installation 11

    What are the steps of next-day boiler installation?

    There are several and different processes involved in installing a boiler. These depend on the complexity or complication your installer might face during work.

    The number of steps differs of course. For instance, replacing a like-for-like combi boiler would require fewer steps than replacing a combi boiler with a system or a heat only boiler. Changing the location of your boiler might also mean more work and extra steps.

    Aside from how complicated the work can be, three main steps are necessary for the installation of your new boiler.

    First Step: Removal of the old boiler

    Before a heating engineer can start with the installation of your new boiler, the old line will need to be removed.

    This can be made easier for the boiler engineers if you clean the space around your boiler to make sure that they have easy access to your boiler.

    If your boiler is fitted in the attic, then it should be accessible via a set of stairs and a safe walkway, and the room should be lit sufficiently. For a more complicated boiler fitting or the relocation of a boiler, the heating engineer may need to remove old pipework and radiators, before installing the new boiler.

    Second Step: The installation of your new boiler 

    After the removal of the old boiler and pipework, the heating engineer will start with the installation of your new boiler and its pipework. This step might be extremely quick, depending on how much work is needed and how complex the job ahead might be. It will not take a long time if you are getting a like-for-like boiler.

    Third Step: New boiler product tour

    A product tour will take place after the completion of the installation process. A heating engineer will check to make sure that your boiler has been properly installed. Then he will show you the ropes. You will be instructed on how to use the controls, the features of your new boiler and how to set a schedule for your boiler to be turned off and on. Make sure to ask the heating engineers about anything that you might need help with. Taking notes might also help you in the long run to maintain your new heating system.

    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.