No longer made
You can’t buy a new back boiler to swap in. When it goes, the heating has to move somewhere else.
Back boilers · Croydon
Back boiler replacement in Croydon
Still got a boiler hiding behind the gas fire? It has probably done decades of work, but back boilers are no longer made and parts are scarce. Replacing yours on your own terms beats a rushed job in a January breakdown.
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- About 2 minutes
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- Used only for your quote
Fixed written price
- Gas Safe No. 567789Check us on the register
- Fixed written quoteThe price you agree is the price
- City & Guilds certifiedTrained and qualified
- Fully insuredPublic liability cover
What a back boiler is
The boiler in the chimney breast
A back boiler sits in the fireplace opening, behind a gas fire, and uses the chimney as its flue. It heats the radiators and a hot water cylinder upstairs, usually with tanks in the loft. The Baxi Bermuda is the classic, and you’ll still find plenty in Croydon’s 1930s semis.
They were built to be tough, and many have outlasted several kitchens. But they haven’t been made for years, they don’t condense, and when a part fails now there’s a fair chance nobody has one. That’s when people end up converting in a hurry, in the cold.
Replacing one is a bigger job than a normal boiler swap, because the boiler has to move out of the chimney. It’s also a chance to rethink the whole system. See boiler conversions for how converting to a combi works in general.
Why replace it
Why most owners don’t wait for it to fail
Parts are scarce
Repairs increasingly depend on whatever parts are still around. A failed part can mean no heating while you plan a replacement.
Old, non-condensing design
A modern condensing boiler with proper controls uses less gas to heat the same house.
Your fireplace back
With the boiler gone, the chimney breast is yours: board it, open it up, or fit a new fire.
The job
What a back boiler replacement involves
Usually 2 to 3 days, depending on where the new boiler goes and how much comes out of the loft.
- 1
Choose the new position
Usually the kitchen, sometimes a utility room or upstairs cupboard. It needs an outside wall or roof route for the flue and a drain for condensate.
- 2
Cylinder and tanks out, if converting
For a combi, the cylinder and loft tanks are drained and removed, and the hot and cold water re-piped from the mains.
- 3
Fire and back boiler removed
The gas fire and boiler come out of the fireplace, the old pipes are cut back and the gas supply to the fireplace is capped.
- 4
New boiler in, fireplace left safe
The new boiler is fitted, the system cleaned and commissioned, and the opening left safe and tidy for you to finish how you like.
Where you end up
Three ways to replace a back boiler
The right choice depends on your bathrooms and your mains water, not on what you had before.
| Option | What changes | Suits |
|---|---|---|
| Combi | Cylinder and loft tanks go. Hot water straight from the mains | Most 2 and 3 bed homes with 1 bathroom and decent mains flow |
| System boiler and cylinder | The small heating tank goes, and the cold tank too with an unvented cylinder | Homes with 2 or more bathrooms used at once |
| Regular boiler | Tanks and cylinder stay. Only the boiler moves | Low mains pressure or flow, or keeping disruption down |
All 3 need a new boiler position, because a modern boiler can’t go back into the fireplace.
Before you choose anyone
Six questions to ask any boiler installer
Including us. A good installer will be glad you asked.
- 01
“Can I see your Gas Safe ID card?”
Check the card is current and covers gas boilers. It’s on the back.
- 02
“How have you sized the boiler?”
A good answer mentions your bathrooms, hot water use and water flow, not just bedrooms.
- 03
“Is the price fixed, and what isn’t included?”
You want a written price that lists the work, not an estimate that grows on the day.
- 04
“Will you clean the system first?”
Fitting a new boiler to dirty water shortens its life and can affect the warranty.
- 05
“Who registers the warranty and notifies Building Control?”
Both should be done for you, in your name.
- 06
“What happens if something goes wrong after you leave?”
Know who to call, and how the warranty works with the installer.
Who you’re dealing with
Don’t take our word for it. Check us.
Anyone working on gas in your home must be on the Gas Safe Register. It takes thirty seconds to check, and you should check whoever you use.
- 1Go to the Gas Safe Register’s “Find an engineer” page.
- 2Enter our registration number, 567789.
- 3On the day, ask to see the engineer’s Gas Safe ID card. The back lists the work they’re qualified to do.
Gas Safe registered
Registration number 567789. Required by law for anyone working on gas appliances.
City & Guilds certified
Formally trained and qualified in plumbing and heating.
Fully insured
Public liability cover for work in your home.
On Track Plumbing & Heating Ltd
A registered limited company, not a one-off trader. Your quote and paperwork come from the company.
Near you
Back boiler replacement across Croydon
What the job usually looks like in the homes of each area, from the people who do it there.
FAQ
Back boiler questions
What happens to the chimney and fireplace?
We remove the boiler and fire, cap the gas and leave the opening safe. You can then board it up, open it for a new fire, or ask about a new gas fire on your quote. If you close the fireplace up, a builder can advise on keeping the chimney ventilated to avoid damp.
Can I keep a gas fire in the fireplace?
Often, yes. Once the back boiler is out, a new gas fire can go in if the chimney and fireplace suit it. Mention it in the quote form message box and we’ll include it in the price.
How long will I be without heating?
The job usually takes 2 to 3 days, and you’ll be without heating and hot water for some of that while the old system comes out. Tell us in the quote form if anyone at home is vulnerable to the cold, so we can plan around it.
Do I have to convert to a combi?
No. If you have several bathrooms or weak mains water, a system or regular boiler keeping a cylinder may suit you better. The boiler still has to move out of the fireplace either way.
Does an old gas fire contain asbestos?
Some older gas fires, back panels and fire surrounds do. You can’t tell by looking, so an old fire should be checked by an asbestos surveyor before removal. Tell us its age and we’ll plan the job around it.
Guides
Read before you decide
- Choosing a boilerWhat is a back boiler?What a back boiler is, how to tell if you have one, why they were fitted in 1930s and post-war homes, and what replacing one with a modern boiler involves.Read the guide
- InstallationHow long does a boiler installation take?How long does a new boiler installation take? Like-for-like swaps are usually done in a day, moves and conversions take 1 to 3 days. What makes a job longer.Read the guide
- Choosing a boilerSigns you need a new boilerThe signs a boiler is reaching the end of its life: age, repeat breakdowns, obsolete parts, leaks, noise, soot or a yellow flame, and what to do.Read the guide
Everything we do
New boilers
Conversions
Repairs & servicing
Get a price to replace your back boiler
A photo of the fire, one of the cylinder and a note of where you’d like the new boiler is enough to start.