There are only two types of people with back boilers; the dying, and the recently dead. The exact same two states than can be applied to any back-boiler itself 🤔
What the eff is a Back Boiler?
A back boiler is a heating device which is fitted in the structure behind a household fireplace, enabling it to provide heat to the house for central heating and also providing hot water.
The boilers were made famous in and around the 1960’s because they were able to be tucked away out of sight, taking up less room in what were often smaller houses.
As well as the size advantage they held over regular boilers, they were also considerably less expensive.
Fundamentally, in 2024 - they’re old, crap, often unsafe and can’t legally be replaced or repaired anymore. When it dies, you need to replace it - likely with a combi boiler. 👇👇
Get a quote for that here. 👈👈
Back Boiler Replacement Key Points:
Back boilers are outdated and inefficient heating systems.
They are located behind fireplaces and provide hot water and central heating.
It is now illegal to install back boilers so they must be decommissioned and replaced with an alternative.
Reasons to replace back boilers include low efficiency, high costs, and safety concerns.
Replacing with modern systems saves energy and improves heating.
Upgrades offer efficiency, control, and potential energy-saving incentives.
Costs vary; obtain multiple quotes and consider warranties.
Get your back boiler replacement quote here.
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Removing a back boiler, what happens?
These types of boilers are no longer fitted or replaced by heating engineers in like-for-like swaps due to their inefficiency and in some rare cases, the safety risk they pose.
If a back boiler can no longer be repaired (highly likely if it's broken!), you'll need to have your system upgraded and replaced with either a conventional boiler or a modern combi boiler.
It’s time to leave the 1960s behind, so put down your mini skirt and upgrade to a real boiler.
After upgrading, you'll likely notice significant savings on your energy bills and much faster hot water.
So if you're a big fan of your back boiler and it's finally broken down after years of reliability, unfortunately, you won't be able to have it replaced.
Here's a snapshot of our prices for a typical, back boiler to combi boiler conversion (not replacement);
Boiler Model | Price |
|
Worcester Bosch 4000 | £2,790 | |
Viessmann Vitodens 050-W | £3,039 | |
Viessmann Vitodens 100-W | £3,370 | |
Viessmann Vitodens 111-W | £3,967 |
At the above prices, we will reconfigure the pipework to be compatible to work with your new combi boiler.
You'll also get a brand-new boiler filter and full chemical flush alongside upgraded heating controls. We also offer a pro flush if you choose it as an add-on, this is essentially a deep clean of your boiler and heating system.
We only offer a power flush for your heating system - it’s not an option to combine plumbing services with your combi boiler installation.
If you're struggling to get the total lump sum together, we can spread the cost for you with low monthly payments.
Check our boilers on finance guide for more information on pay monthly options.
BAXI Bermuda Back Boilers
If you've got a back boiler, you'll more than likely have a BAXI Bermuda. They absolutely dominated the back boiler market back in the day, and to be fair, did a cracking job. It’s why you still have one and it will be emotional to let go of it.
BAXI Bermuda back boilers are super reliable (or, were) and very affordable (hence their popularity).
To check if you've got a BAXI Bermuda back boiler you'll need to get on your knees and pull down the flap underneath it, you should see a label or model number (usually on a small sticker).
Unfortunately, parts for BAXI Bermudas are practically non-existent and have all but disappeared.
Back Boiler Removal/Replacement Costs
If you've decided to get your hot water back upgrade your heating system and have a modern boiler installed, then you will have two options regarding your old back boiler.
Check our new boiler costs guide and boiler size calculator for a better understanding of your exact situation.
#1 Remove the entire back boiler system & replace it with a modern combi/regular boiler
As mentioned earlier, the back boiler is tucked away behind the structure of your fireplace and chimney. On the plus side, it’s a better spot than the middle of your living room for decades.
Removal of the back boiler unit will include the fire being removed and the back boiler being disconnected from the pipework and existing flue system - which will also be removed.
The pipework will also need to be reconfigured to work with the combi boiler which is a simple process.
In most instances, the fireplace and hearth can stay in position. When the fire and BBU have been removed you will be left with a square hole which can be quite easily bricked up or boarded over by a third-party builder.
Bear in mind this will need a vent to stop dampness from occurring behind the patched-up fireplace.
A round-up of what will potentially be involved includes:
Removal of fireplace/mantle
Removal of the back boiler system
Rebuilding of mantle area (likely to require third-party services)
Installation of combi boiler in a new location
Likely installation of new pipework for a combi boiler
Work required for new combi's flue system - your old back boiler will have used the chimney as its flue system
If your wife loves redecorating, you could always frame it as a fun project - keep those third-party services at hand, though.
Get a fixed online quote for a back boiler conversion.
Heatable will of course, include the cost of your combi boilers new location within our fixed price.
Curious to know which boiler brand performed worst? Find out in our report of the worst boilers.
Cost of Back Boiler Removal & New Boiler Installation
Taking into account all of the aforementioned work that's required, having a back boiler removed and a combi boiler fitted is probably the most expensive installation and you should be prepared to pay no more than £3,500-£4,500.
A considerable expense but new boilers can be financed and you're likely to save up to £300 a year with your upgraded heating system.
Decommission the Back Boiler and Have a New Combi/Regular Boiler Installed
The fire itself will need to be removed unless the pipework can be accessed via boxing usually at the side of the fireplace which can affect the décor.
No matter if the fire and BBU are left in place they will both need decommissioning (gas supply cut from them both).
It is typically only advisable to leave the old components in position if the BBU is too large to remove due to it being built around in the past.
The pipework where accessible will be re-configured to be compatible with a combi boiler.
You can check with us in advance if it's possible to have the BBU removed in full, or if leaving it in place after decommission is more viable.
You'll still need all of the above work carried out but won't have the added cost of removing the old system entirely and rebuilding the mess this can't help but create.
It also means that buyers in 100 years will be uploading a video on TikTok marvelling at the mysterious machine they found behind the fireplace.
Related domestic energy guides:
Cost of Back Boiler Decommissioning and New Boiler Installation
Having the back boiler decommissioned instead of removed entirely could potentially save you up to £1000 so you're still looking at a total conversion cost of around £3,000 and £4,000.
Assuming a Gas Safe engineer has declared it safe to decommission the back boiler without its removal then the choice would be yours.
Learn all about combi boilers in our what is a combi boiler guide.
If you're looking to pay for your back boiler upgrade on finance though, it's worth considering that a saving like this may not affect your monthly repayments so significantly.
Get a fixed online quote for a back boiler conversion.
Note: Thinking about an immersion heater instead? Read our guide to find out how they compare to central heating boilers.
Time for a combi boiler? What now?
You may need a new boiler.
You may need it fast, and with affordable monthly payments.
You may even need it from a company with top end local engineers, with 10,000 Trust Pilot reviews to back them up. Plus a Which? Trusted Trader award for good measure.
You may need a new boiler quote from us, Heatable 😘
