How long does it take to fit a new boiler?

Picking out and fitting a new boiler can be a stressful time as a homeowner, especially if you’re unsure of the process, how long it can take, and any problems that may arise during a boiler installation. Fortunately for you, toasti has a helpful guide detailing how long it takes to fit a boiler, so continue reading to learn more.

How long does it take to fit a boiler?

On average, the installation of a new boiler can take anywhere from one to three days. The time taken can vary depending on a number of factors, including whether the boiler is being moved to a different part of the house, the size of the boiler, and if any additional work needs to be done, such as fitting new pipes.

However, a simple installation should only take one day.

Some installation companies may need time to complete a survey of the area in which the new boiler is being installed, which can add to the installation time.

How long does it take to replace a boiler?

Replacing a combi boiler in the exact same spot as the previous boiler is a relatively easy and smooth process for a qualified professional. Assuming everything goes smoothly, the combi boiler replacement should take between four and six hours.

Replacing a system boiler with a combi boiler

A like-for-like replacement of combi boilers is the bread and butter for gas engineers. However, replacing a regular/system boiler with a combi is more time-consuming.

This process can take up to two whole days because of the extra work involved, including removing the water tank that’s no longer required and any new pipework.

Replacing a back boiler with a combi boiler

Replacing a back boiler with a combi boiler can take two or more days.

First of all, a back boiler needs to be relocated to somewhere else in the house. All boilers need a flue pipe to ventilate harmful gases, such as carbon monoxide, to the exterior of the house. Back boilers vent these up a chimney, so you’ll need a new flue installed at the location of the new boiler.

All of the work of relocating the boiler, fitting a flue pipe and any new piping means a back boiler replacement not only takes longer to complete, but is also much more expensive than a combi-for-combi swap.

Installing a smart thermostat

Smart technology is in most people’s houses nowadays. Smart thermostats are a great way of reducing energy costs and simplifying the use of your central heating system.

Many companies now offer a smart thermostat installation alongside your new boiler, but this does also add to the installation time. It doesn’t take long, but it still adds cost and labour.

Problems you might face during installation

Unfortunately, boiler installations aren’t always plain sailing and can bring about some problems, such as:

  • Leakages
  • Low pressure
  • Boiler won’t switch on
  • Pipes banging
  • No heating or hot water

Fortunately, the Gas Safe registered engineer that has taken the time to carefully install your new boiler is trained to detect and fix any issues. If it’s found that your new boiler is facing some of the above problems after installation, the engineer that fitted the system will fix them.

They’ll never leave your house without ensuring the entire system is working correctly.

What if your current heating system doesn’t meet Gas Safety Regulations?

As a result of over 60 deaths a year from carbon monoxide poisoning in the UK, the government set up Gas Safety Regulations to prevent mistakes from causing needless deaths in future.

One of the new regulations that have come into force in recent years is changing the minimum gas supply pipe size from 15mm to 22mm. If the engineer fitting your new boiler discovers that your gas supply pipe does not fit the new regulations, they will have to fit a new pipe, which adds to the installation time.

Boiler installation by toasti

With over 30 years of experience in new boiler installations and boiler replacements, including combi swaps and back boiler conversions, toasti is on hand to help you find the best new boiler for you and your home.

All of our installation engineers are trained to a high standard and are Gas Safe registered for your peace of mind. Plus, our helpful engineers will explain how your new boiler works, troubleshoot any problems, and leave your home as clean as they found it.

It’s quick and easy to get a quote for a boiler replacement with toasti. Just speak to a member of our heating team and we’ll take care of the rest. Contact us on 0161 527 7326, or email us at