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New Boiler Installation: Costs and Other Considerations

Getting a new boiler installed is a big job, and one that can be stressful and confusing without all the facts. A few simple pointers on the different types of boilers and the price of installation could be all you need to make the right decision for your home. 

Regularly maintaining your boiler ensures your home is never without heat and hot water. Keeping it in good working condition will help it run efficiently without costing you any extra money. 

This article will talk you through your new boiler installation, discussing when you might need to look for a new boiler, the different models and what makes the best fit for your home, and how much it’s likely to set you back. 


Do I Need a New Boiler?

There are a number of different signs that your old boiler might be on the way out. Although the upfront cost of a new boiler might be off-putting, it’s likely a faulty boiler will be adding more money to your energy bill and doing a poor job of heating your home. 
Boilers don’t last forever. If you find you’re experiencing any of the following issues, it might be time to start looking for a replacement. 

Regularly needs repairs: You should look to get your boiler serviced once a year. If you find yourself regularly paying for repairs and new parts, then you will probably need a new one. 
Winter can be particularly problematic for boilers. If you find yours failing over the colder months, follow our guide for tips and advice on the best course of action.  

It’s old: Boilers tend to have a lifespan of around 10 years. It might seem to be functioning fine but the older it gets the more likely it is to break down. It will also be less efficient than a newer model, so replacing it may pay off in reduced energy bills. 

It’s leaking: Any leaks should be taken very seriously. Water damage can be a serious threat to your home, but there is also a risk of a carbon monoxide leak, which can be life-threatening.

Fluctuating water temperature: Water taking a long time to heat up, or the temperature fluctuating when you run the hot tap, can be signs your boiler might be on its way out. If repairs don’t fix it then you should look into a replacement. 

Unusual noises: Worn down parts can lead to knocking, popping or hissing sounds when your boiler is in use. If these are a reoccurrence, then it could mean you need a new one. 

If you want any further advice on whether you need a new boiler for your home, you should call out an engineer to get a professional opinion. 

Different Types of Boilers

There are three basic types of boilers that you should consider when looking for a replacement. The right choice for your home depends on your existing heating system, your heating requirements and the space you have available. 

Combination Boilers 

Available in electric or gas, combination, or ‘combi’ boilers are the most popular choice in the UK. They provide instant hot water and make good space savers as they don’t require the installation of a tank or cylinder. They’re best suited for smaller homes when it’s likely people aren’t going to need a lot of hot water all at once. 

Conventional Boilers 

Also known as a regular boiler, conventional boilers are a more traditional model. They’re fitted with a tank and a cylinder, making them better suited to larger homes that might need a lot of hot water at the same time. If you have a smaller home you may have trouble finding space to install the tank and the cylinder, as they’re usually kept in the loft. Unlike the combi boiler, if you run out of hot water it will take time to take water from the cold tank and heat it. 

System Boilers 

A system boiler is a hybrid between a combi boiler and a conventional boiler. Similar to a regular boiler, it heats and stores water in a cylinder, but it doesn’t require the cold tank. They offer greater hot water comfort and higher flow rates for baths and showers. They make a good fit for larger homes with a high hot water requirement, but you will still need to find space to store the cylinder. 


Choosing Your Boiler

Once you understand the different types of boilers, there are a few key things you should consider before deciding on your new boiler. 

How much water do you need?

You need to consider your water usage before deciding on the right boiler for your home. Combination boilers are ideal if you live in a small home and won’t need to use a lot of hot water at the same time. Conventional or System boilers provide enough water for larger homes where you will need to run multiple taps at a time, but you will have to wait for the water to reheat when it’s all been used. 

How much space do you have?

If space isn’t an issue, then conventional or system boilers are attractive options, but if you will struggle to find space for a cylinder and water tank then it could be worth considering a combi boiler.  


Where will you keep the boiler? 

Installing a new boiler is made much easier if it’s kept in the same place as the old one. If you’re replacing your existing boiler with an alternative type, you need to consider where you’re going to store it and the added costs that may come with the installation.

What is it going to cost?

You should also consider your budget when making a decision on a new boiler. There can be added costs – for example, installing a new model of boiler can lead to extra installation costs. It’s cheaper to replace your boiler with the same model, so if you were happy with the water use supplied by your previous boiler, this could be worth considering. 


Boiler Installation Costs

Different scenarios and added extras can affect the cost of a new boiler – this guide will talk you through the different costs, broken down by different models. 

Combination Boiler Prices

When considering a combi boiler, there are a number of different variables that can influence the total cost of your new boiler. This includes the size of your property, installation costs and any extras you may need. The different prices are included below: 

Size of your property
Small home: £600 - £1,500
Semi-detached or terraced: £700 - £2,000
Detached home: £900 - £3500

Cost of Installation

Type of installation/Estimated boiler installation cost     

Replacing existing combi:  £600                                                   
Replacing a conventional boiler: £700
Install combi in a new location: £1,100



Replacing an old boiler can sometimes result in added costs – for example, you may require a power flush to remove any sludge that has built up over the years. To discuss any extra costs, you may want to consult an engineer, examples of what you could need are

Item/Estimated cost

Power flush: £500
Moving pipes:£200
Thermostat: £200
Chemical flush: £300
Radiator (each): £100

Conventional Boiler Prices

Conventional boilers are normally found in homes with a traditional heating system. If this is the case, then it makes replacing them easier and less costly for the homeowner. If you don’t already have a conventional boiler it will cost you a lot more to install the cylinder and water tank, so you need to be sure you’re making the right decision for your home. 


Type of installation/Estimated new boiler cost 
Replacing existing conventional boiler: £1,500-£2,500
Replacing combi boiler: £2,200-£3,400
New installation: £2,500-£3,700

System Boiler Prices

A modern option for households who need to use a lot of hot water at once. Similar to conventional boilers, if you already have a system boiler then replacing it with the same model is the most cost-effective option. If you want a conventional boiler installing, you must pay the added cost of fitting a water tank. 

Type of installation/Estimated new boiler cost
Replacing existing system boiler: £1,600-£3,000
New installation: £2,000-£3,500

The Installation Process

If you’re unsure on how the installation process works, here is some insight as to how professional engineers will go about installing your new boiler. 

  1. They will begin by checking your current water pressure, the number of bathrooms and radiators, as well as taking a look at your current boiler and its position
  2. A straightforward like-for-like swap can be finished on the day, whereas a more complex job will prolong the installation. Once work is finished, the engineer will talk you through your new boiler and how it works. 
  3. After the job comes payment. Our advice would be to get a fixed quote before work begins to avoid any surprise additions. Use our approximate costs to give you some insight into how much it’s going to cost and what the best option is for you financially. 
  4. A lot of companies give you documents to prove compliance. It can be worth asking for these if you haven’t received them. 
  5. Many companies also offer you a guarantee on the services. If you have any queries about the work that has been done, you should chase this up as soon as you can. 

New boilers are important investments and you should take your time and do your research to ensure you make the right decision for your home. Hopefully this article has given you guidance on what model you need and how much it’s going to cost you. If you’re in need of further information you should seek the advice of a professional engineer.