Planning for a new boiler installation? One of the most common questions we receive from homeowners across Bolton, Bury, Burnley, and Rossendale is: How long does it take to fit a new boiler?
It’s a fair question, after all, replacing a boiler isn’t something most people do very often. And since it can mean a temporary disruption to your heating and hot water, understanding what to expect helps you plan. This guide breaks down how long boiler installation takes, depending on the type of job, your current setup, and whether any additional work is involved.
How Long Does a Boiler Installation Take?
There’s no one-size-fits-all answer. Boiler installations can take anywhere from a few hours to several days, depending on:
- The type of boiler being installed
- Whether you're switching boiler types (e.g. combi to system)
- Whether the boiler is staying in the same location or being moved
- The condition of your existing pipework and system
- Whether system upgrades are needed (such as new controls or radiators)
At JS Gas & Oil, our heating engineers typically see installation times ranging from 4 hours to 3 days. Below, we outline common scenarios to help you get a clearer picture.
Straight Boiler Swap – 4 to 6 Hours
This is the quickest and simplest type of boiler installation. If your new boiler is the same type and brand as your current one and is being installed in the same location, it's considered a like-for-like swap.
What’s involved:
- Removal of the old boiler
- Fitting of the new boiler in the same place
- Connecting to existing pipework and flue
- Testing and commissioning the new system
In most cases, our engineers can complete a straight boiler swap in half a day, minimising disruption to your daily routine. It's also typically the most cost-effective option.
Boiler Relocation – 1 to 2 Days
If you want to move your boiler to a different location in your home, such as from a kitchen cupboard to a loft or utility room, the job becomes more complex and time-consuming.
Why it takes longer:
- Old boiler needs to be safely disconnected and removed
- New pipework (gas, water, and heating pipes) needs to be run to the new location
- Electrical wiring and thermostats may need updating
- Structural considerations, such as drilling for flue installation, may be required
Depending on the difficulty and layout of your home, relocating a boiler usually takes between 1 and 2 days.
Changing Boiler Type – 2 to 3 Days
Upgrading or changing your boiler type involves a full system conversion and is often the most complex option. For example:
- Combi to system boiler: Requires adding a hot water cylinder
- Combi to heat-only: Requires a cold water storage tank and expansion tank
- System to combi: May involve removing tanks and cylinders
This kind of job often involves:
- Extensive plumbing and heating pipework modifications
- Possible electrical upgrades
- Removal of tanks (where applicable)
- Installation of new controls and thermostats
Expect a full conversion to take between 2 and 3 days, depending on how much infrastructure needs replacing. Although this is a bigger job, it can be a smart long-term investment if your lifestyle or household size has changed.
Additional Factors That Affect Installation Time
Even within each category, some properties will require more time due to:
- Old or damaged pipework: May need replacing to meet current standards
- System flushing: A powerflush might be recommended to clean sludge from existing radiators and pipework
- Upgrading flue system: Especially relevant in older homes or listed buildings
- Smart controls and thermostats: Adding advanced controls takes extra time but boosts energy efficiency
All these factors can add hours, or even an extra day or two, to your installation.
Can I Speed Up My Boiler Installation?
While the installation itself needs to be done safely and correctly, there are a few things you can do to help the process go smoothly:
- Clear access: Make sure the area around the boiler and pipework is easy for engineers to reach
- Have your heating records ready: If you know the make, model, and history of your current boiler, let your installer know in advance
- Discuss plans ahead of time: Our engineers are always happy to explain your installation timeline so you know what to expect
At JS Gas & Oil, we offer clear, up-front guidance and keep you informed throughout the process.
Professional Advice Tailored to Your Home
If you’re unsure what type of boiler is best for your home—or how long your installation will take—our experienced Gas Safe registered engineers are here to help. Whether you live in a two-bedroom terrace in Bury or a large detached home in Rossendale, we’ll assess your needs and explain all your options clearly.
We also handle:
- Boiler replacements
- Full heating system upgrades
- Smart thermostat installations
- System flushing and cleaning
- Servicing and annual safety checks
Looking to install a new boiler in Bolton, Bury, Burnley, or Rossendale?
At JS Gas & Oil, we carry out fast, professional boiler installations with minimal disruption. From simple swaps to full system upgrades, our Gas Safe engineers have the experience to handle any job. Call us on 07791 802791 or get in touch via our website to book a consultation or request a free quote today.
