How long does it take to fit a new boiler? Average boiler fitting times in the UK

James Elston
Written by James Elston
Updated on 15th January 2024
Posted on 4th December 2023
Topic: Boiler Advice
How long does it take to fit a new boiler? Average boiler fitting times in the UK

How long to install a new boiler or replace a boiler?

Fitting a new boiler installation can take some time, but fortunately, we are experts, therefore we can give you pretty accurate estimates of how long it will take to install a new boiler in your home, depending on your requirements.

Boiler installations are quite complicated as they include the Gas Safe engineer to deal with gas, electricity and water all at the same time, which when mixed can be very dangerous, so you will be glad if the installation takes time as it means it is being completed thoroughly and professionally.

Read more for boiler fitting timescales for new or replacement boilers in the UK.

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The average time to install a boiler

New combi boiler swap1 day
New Combi boiler swap and relocation1-2 days
System to new combi conversion1-2 days
New system boiler1 day
New system boiler with relocation1-2 days
New regular boiler swap1 day
Regular boiler swap with relocation1-2 days
Regular boiler to combi boiler conversion1-2 days

Let’s look at your boiler replacement options and new boiler fitting in more detail below:

how long to fit and replace a boiler

If you are looking for a new boiler, get one fitted as quick as the next-day nationwide, click here to get a fixed price online

One of the most common questions about new boiler installations is how long it will take to replace or install them. This guide gives you everything you need to know about how long it will take to fit your boiler upgrade.

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What do you need to know about fitting a new boiler?

boiler installation diagram

Firstly, It’s important to note that fitting a new boiler isn’t always a simple like-for-like swap. Additionally, you might need to upgrade your current heating system to a new system, replace an old boiler, or switch to a new combi.

For this reason, the time it will take is dependent on your circumstances. That said, this guide will touch on the average installation times and what you can expect at a minimum.

Additionally, the fastest boiler installation is what’s called a ‘like for like swap’. So, all gas boiler fitting must be done by a Gas Safe registered engineer.

Simply, this refers to those who need to replace their current boiler with the same type of boiler. Be sure that this doesn’t mean the same brand, simply the same type of technology.

Therefore, replacing your current combi boiler in the same location calls for a new, modern boiler. You are in luck.

gas safe installer

A like-for-like swap usually takes a Gas Safe heating engineer a day.

If everything goes to plan without any issues occurring, it should take up to 6 hours at the most to fit your new central heating system to meet the full Gas Safe regulations.

How long does it take to replace a boiler?

The common answer is usually 1 to 2 days for moving a boiler or replacing a boiler.

But this answer will vary depending on what work is needed, if your boiler is moving location or if you have a like-for-like boiler.

gas engineer

You won’t typically see one replaced in less than a day. While that seems like a lot of time, it’s because boilers are complicated machines and there is a lot of variation when it comes to boiler types.

Sometimes you may need to move additional pipework or a boiler flue, and all of these tasks take time.

If your boiler was previously leaking water, then you may need some work to repair flooring or areas where water may have dripped on. 

Boilers such as the Megaflo unvented range takes longer to install as many of these installations are new installs. These can take 1 to 3 days dependent on the size of the boiler and home

It will often take quite a while however, if you have a combi boiler, then you will benefit from a much shorter installation time.

So, let’s change the question for a moment how long does it take to fit a new boiler if it’s a combi unit?

How long does it take to install a new combi boiler?

Not to mention, combination boilers, or combi boilers, are hybrid devices that serve as high-efficiency water heaters and a central heating system.

These are the most fitted, modern boilers throughout the UK. Combi boilers benefit from much shorter installations on average.

In comparison to more “traditional” conventional boilers, a combi boiler can usually be installed in 4 – 6 hours.

Moreover, these are usually only useful if you’re replacing an existing combi boiler and want it installed in the same location. Find out what a conventional boiler is here. 

If you are getting a combi installed but currently have an older boiler, such as a traditional back boiler, then installation will take longer.

If you want to relocate the boiler, such as from one room to another, the installation will take longer.

The location is very important when it comes to boiler installation so let’s take a more detailed look at it.

When considering how long it will take to move and fit new boiler, the location will be very important to any engineer’s or surveyor’s estimate.

How long does it take to move a boiler?

If you want the boiler to be kept in the same location, then installation will almost always be quicker, unless the engineer runs into an unexpected problem that is.

However, how long to install or move a boiler will be a much longer job.

Whereas, moving a boiler to a new location will usually require the engineer to change the existing pipework and maybe even install new pipes as well.

This as I am sure you can guess, will add some extra time to your boiler installation.

How much longer this will take can once again can vary quite considerably depending on where you want the boiler moving to.

But on average you can expect it to add half a day to a full day of extra time to your boiler installation.

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How long does it take to remove and install a boiler?

Not only, is the removing and installation process of a boiler is all included in boiler replacement, as removing the old boiler doesn’t take that long. Most boilers are just hung on a wall using a large bracket that can take the weight of the required boiler. If you remove a boiler and the brackets, you will receive a new one with your replacement boiler.

Once the old boiler is removed as the first job, the rest of the job will be installing the new one which as we have said can take from 1-2 days depending on the work involved.

How long does it take to upgrade a boiler?
a rated boiler replacement

Finally, the other main thing that can impact your installation timeframe is whether you are getting a system upgrade or not.

If you’ve never heard the term system upgrade before then don’t worry. It means you are changing the type of boiler.

As previously stated, replacing an older conventional boiler with a new combi boiler will most likely take two days.

However, if you already have a combi boiler and are replacing it with a conventional boiler then installation could take even longer.

The Installation can take around 3 – 4 days in some cases.

combi boiler how long to install

So within a few hours, you can be controlling your heating and room temperature with your phone or tablet if it is a combi swap. But if it’s a bigger job, it could be longer depending on your current boiler system.

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How long for a new boiler fitting time guide

If you are wanting to know how soon a new boiler can be fitted by an engineer, then you’ll be glad to know that we can fit them as soon as tomorrow. Next day boiler installation is available nationwide from us here at Boiler Central.

Combi boiler fittingNext day
Combi boiler and relocationNext day
System to new combi conversionNext day
System boiler fittingNext day
System boiler with relocationNext day
Regular boiler fittingNext day
Regular boiler with relocationNext day
Regular to combi boiler conversionNext day

How do you install a boiler?

If you haven’t gone for our full supply and fit combi boiler service, you may be wondering what you have let yourself in for.

However, if you are considering installing a combi boiler yourself, then we strongly urge that you don’t, as it is illegal if you are not suitably trained in the installation of a gas boiler.

Read the instructions

Installing a combi boiler is complicated and needs to be precise because different makes and models are fitted differently. The instructions will have all the diagrams of fixtures, fittings, layout and components of how to fit the combi boiler.

removing broken boiler and installing a combi boiler

Once you have done this you will be able to figure out where everything goes and think about removing the old boiler and installing the new one.

Remove the old boiler

Before you can install a combi boiler, you will need to disconnect and remove the old boiler from the wall.

Ensure that all gas, water, and electricity supplies are turned off before doing anything. Removing an old boiler isn’t an easy task, however, it should be relatively quick and not take up much of the installation time.

Fit the combi boiler

Once you are happy, you know where all the pipework is and which pipes are connecting to which, you can start to consider fitting the combi boiler to the wall.

If your boiler is wall hanging, it will have a bracket on which it will hang which will need screwing to the wall first. Once this is done, you can hang the combi boiler and start connecting up the copper pipework.

Finish the installation by testing the boiler

Once the combi boiler installation is complete, then you will need to test it and the central heating system to ensure that it is working correctly.

There are several tests, some more obvious than others. You can turn on the combi boiler and check to see if all the radiators get hot, as well as turn on the hot tap to see if you get hot water.

More specialist tests also need to be completed, such as gas pressure and flow, ventilation and if the flue is fitted and working correctly.

This is why it is so essential to get a company that installs boilers daily to ensure that the boiler fitted is safe to use every day.

Which combi boiler to install?

If you are considering a gas combi boiler installation and getting the best combi boiler for your home then you have around 10 to choose from, depending on the size of your home.

If you have a smaller home, the best combi boiler installation will be the Viessmann Vitodens 050-W, whereas if you have a medium-sized home, we recommend the Worcester 4000 combi.

Lastly, large homes with up to 2 bathrooms would benefit from installing a Worcester 8000 40kw combi boiler.

Summary of boiler installation times:

As illustrated, there are many different answers to the question of how long it takes to install and fit a new boiler. Because in most cases, you can expect around 1 day on average. At most, it usually takes 2 days especially if you need a new gas supply pipe too.

If you are doing the like-for-like and swapping to the best combi boiler, you can expect your installation to be quick, often within a few hours. So the rest of the time spent after the actual fitting of the boiler will be safety checks by the Gas Safe registered engineer.

What about a boiler service, how long does it take?

Another commonly asked question is, how long does it take to service a boiler? Boiler services should happen annually to keep your warranty valid and usually takes around 1 to 2 hours and you can expect boiler service costs to be around £100.

Additionally, if you are looking for a new boiler, get a fixed boiler price online now.

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Above all, you can even purchase your boiler online and choose your installation date from our live calendar.

You can pay securely by card or even apply for boiler finance online for £17 per month within minutes.

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Written by
James Elston
James Elston Director Of Boiler Central
Posted on: 4th December 2023
Topic: Boiler Advice

James Elston is our resident boiler replacement and heating expert here at Boiler Central. With over 20 years experience in the boiler installation industry, James ensures that he knows everything there is about our Gas Safe boiler installations, energy saving and home heating solutions. This can be from simply procuring the latest best combi boilers, to reviewing and ensuring that Boiler Central maintains the highest standards across our boiler installation company.

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