How to prepare your home for a boiler replacement

Installing a new boiler in your home can sometimes be a long and disruptive process, especially if it’s being installed in a different location than your old boiler.

But, to minimise installation times and maximise efficiency, there are things you can do to help the Gas Safe registered engineer who'll be carrying out the work.

In this guide, we explore four tips to help you prepare for your boiler replacement and ensure the installation process is as smooth and straightforward as possible. But first, let's explore why preparing your home for its new heating system is a good idea.

How to prepare for boiler installation

Before the Gas Safe engineer fits your new boiler, complete the following tasks to ensure the boiler installation process goes as smoothly as possible.

1. Clear the area and a pathway to your boiler

Whether you’re having your new boiler installed in the same place as your old one or opting to have it moved to a new location, you need to make sure the area around your boiler is clear. You should also ensure the existing system, radiators, water stop tap, and gas meter are accessible and that the new boiler location is clean, too, if it’s being relocated. Additionally, if the new boiler is to be installed in the loft, the floor in the loft would need to be boarded and also has a fixed light and a fixed loft ladder.

Once you've cleaned around where the boiler will be installed, you must ensure a pathway from there to the front or back door. The engineer will likely be nipping in and out to their van to fetch various tools, not to mention carrying the new boiler into your home. Guaranteeing ease of access reduces installation time and makes the process much easier and safer.

2. Identify any areas of concern

Before installing the boiler, you should identify additional concerns in your heating system. This could include rusty pipework, problematic radiators or inconsistent pressure levels. Basically, anything you'd like the engineer to look at, make them aware of it before they get to work installing your replacement boiler.

Flagging any issues will mean the engineer can advise or could even fix them while they install your boiler or organise a time to come back and resolve the issue.

3. Keep little ones out of the way

As well as clearing space for your boiler to be installed, you need to make sure children and pets are kept out of the way. This is more of a health and safety concern as opposed to something that will increase productivity, but it may help the engineer concentrate on their work.

Pets, in particular, can be a hazard, so it's important you keep them away from the work area and ensure the engineer has enough space to work.

4. Identify your home’s fuse box or consumer unit

Whether you’re getting a system, standard or combi boiler installed, every boiler needs to be connected to your home’s electricity supply. Contrary to popular belief, even gas and oil boilers rely on electricity to ignite, so you’ll need to locate the boiler's electrical isolation point (fused spur) and potentially your property’s fuse box before your engineer arrives. 

If possible, make it easy for your engineer to access the boiler’s fused spur or fuse box by clearing a safe pathway to the switch or fuse box then show them the specific switch that controls your boiler. Making sure the engineer only flips the necessary fuse will prevent other areas and appliances in your home from ending up without power.

What is the new boiler installation process?

Once you've cleared the area where the boiler will be installed, found the fuse and any areas for concern, and got your pets or kids out of harm's way, the installation can begin. But what happens when the engineer arrives at your home with a new boiler? Here's what happens in seven simple steps:

1. The boiler and/or system electricity supply needs switching off: Isolating the electrics before the installation ensures safe working, and the electricity supply may require turning off at different times during the installation to install new controls or even a new fused spur.

2. The gas will need isolating and testing for leaks before the installation: Testing for gas leaks before installation is important to identify any unsafe situations with the supply and, where practical, resolve and/or repair.

3. The system is drained and the old boiler removed: The existing system will be firstly drained of all water, and the old boiler will then be removed. Removing smaller appliances, like combi boilers, can be relatively straightforward, but larger heating systems, e.g. those with water storage tanks/cylinders, will take longer.

4. The area is checked and prepared: During this process, the engineer will assess the boiler's flue system to ensure it complies with the manufacturer's instructions and building regulations or what needs to be done to ensure the new flue complies.

5. The heating system is flushed and cleaned: Following British standards, engineers should flush your central heating system each time a new boiler is installed.

6. The pipework is upgraded: If you want your boiler to be moved or the pipework looks worse for wear, the engineer will upgrade some or all of the pipes, including the gas pipework, where necessary.

7. The new boiler is installed, and accessories are fitted: Straightforward installations can be completed within a day, but more complicated work can be significantly longer. Once the boiler is installed, the engineer can work on fitting accessories, like system filters, condensate pumps and additional required flue lengths.

8. Checks are carried out: The boiler will be tested to ensure it works properly and should be commissioned in accordance with the manufacturer's instructions.

9. The boiler is registered: Once installed, the engineer will register your new boiler with Gas Safe, the relevant local authorities, and the boiler manufacturer to validate the appliance's warranty. At BOXT, we do this for you!

Check out our blog for a more detailed look at what happens when a new boiler is fitted, including whether your water and gas supply will need to be turned off.

What is the average installation time for a new boiler?

The time it takes to install a boiler depends on the size and scale of the installation, but it's typically between one and two days. Explore the factors that can prolong the process in our 'How long does it take to fit a new boiler?' guide.

Is it better to repair your current boiler or replace it?

Deciding whether to replace or repair your boiler is a tricky decision; on the one hand, the short-term cost of repairing your boiler may be cheaper than a new model; on the other hand, a new appliance offers long-term peace of mind.

To help you make an informed decision, we explore the pros and cons of each side in our 'New boiler vs boiler repair' blog.

Get your next boiler from BOXT

Still on the search for your next appliance? Take a look at how to choose your perfect boiler for tips on making the right purchase.

Ready to get your new boiler? With BOXT, you could have a new appliance installed as early as tomorrow. Use our Find a Boiler tool to get started and look forward to a more affordable, more comfortable home.