Back boiler removal and replacement
Out with the fire-and-boiler combo, in with something efficient.
A back boiler sits behind a gas fire in the living room, usually with a hot water cylinder upstairs and a cold tank in the loft. Plenty of them have run for decades. When yours starts to fail, parts get hard to find and the running costs are hard to ignore. We take the old unit out, make the fireplace safe and fit a modern condensing boiler in a better spot, with a fixed quote agreed before we start.
Signs it is time to replace your back boiler
Back boilers were common in homes built from the 1960s to the 1980s, and many of them are still going. Age alone is not a reason to rip one out. These are:
- An engineer has struggled to find parts on a repair
- The pilot light keeps going out, or the flame burns yellow rather than blue
- Soot or brown staining around the fire front
- Your heating bills keep climbing while the house feels no warmer
- The fire has been condemned or capped off at a safety check
Where does the new boiler go?
Most people move it out of the fireplace altogether. A wall-hung boiler in the kitchen, utility room or an airing cupboard is the usual answer, because it needs an outside wall or roof for the flue and a drain for the condensate pipe.
Moving the boiler adds pipework, so we plan the shortest sensible route on the survey. If you have a particular spot in mind, like the loft, have a look at our boiler relocation page as well.
Combi or system boiler?
This is the big decision. Going to a combi removes the cylinder and the loft tank, which frees up the airing cupboard and gives you hot water on demand. It suits smaller homes with one bathroom. We cover that work on our combi conversion page.
If you have a larger family or more than one bathroom, keeping a cylinder with a system boiler is often the better call. We will give you a straight recommendation after we have seen the house and asked how you use your hot water.
What happens to the fireplace
Once the back boiler and fire are out, we cap the gas supply safely and leave the opening ready for you. Some people fit a new fire, some have a builder board it up and plaster over it, and some leave it open as a feature.
If you want to keep a gas fire there, we can talk that through on the survey. The old chimney or flue needs checking before anything new goes into it.
What happens, step by step
Survey
We look at the back boiler, the cylinder and tank, and where a new boiler could sit.
Fixed quote
You get one written price, with the new boiler position and pipe runs explained.
Removal and install
Usually two to three days depending on how much pipework changes.
Handover
We test everything, show you the controls and register the warranty.
What is included
- Survey of the existing system, chimney, gas supply and new boiler position
- Safe removal of the back boiler and fire front, with old parts taken away
- Gas supply capped at the fireplace
- New condensing boiler fitted, with new flue and condensate pipe
- System cleaned, magnetic filter fitted and controls set up
- Old cylinder and loft tank removed if you go to a combi
Back boiler removal and replacement FAQs
How long does a back boiler replacement take?
Typically two to three days. Taking out the old unit is quick. The time goes on running new pipes to the new boiler position, fitting the flue and, if you go to a combi, removing the cylinder and loft tank.
Can I replace my back boiler with a new back boiler?
It is rarely the right move. New gas boilers have to meet modern efficiency standards, and very few back boiler units are still made. In nearly every home we see, a wall-hung condensing boiler elsewhere in the house is the more sensible choice.
Will there be much mess?
Some. Pulling out a fire and back boiler creates dust, and new pipework sometimes means lifting a few floorboards. We use dust sheets, keep the work area tidy and clear up each day. Any making good after we finish, like plastering the fireplace, is usually a job for a builder or decorator.
Is it worth replacing a back boiler that still works?
If it is safe and parts are still available, you can keep running it. Most owners switch when a repair bill lands or a part becomes unobtainable. A new condensing boiler should use less gas, but we will not pretend to know your exact savings without seeing your usage.
Get a fixed price for your home
Tell us about the job and we will arrange a free survey.