Mon–Sun, 8:30am–5:30pminfo@harrisonejonesheating.co.uk 07523 7382850151 384 5908 HomeAboutServices Areas ReviewsContact Us07523 738285Get a Free Quote New Boilers Fully Fitted from £1,299 with Immediate Installation and a FREE Gas Safety Certificate HomeBoiler SupplierBack Boiler Removal & ReplacementBoilers # Back Boiler Replacement in Liverpool: Removed, Converted and Certified Take out an old back boiler hidden behind the fireplace and replace it with a modern combi or system boiler, with the chimney, flue and gas supply upgraded properly and the fireplace made good afterwards. Get a Free Quote07523 738285 Gas Safe registered no. 576059 · new boilers fully fitted from £1,299 with a free Gas Safety Certificate Gas Safe registered Registration no. 576059 · licence no. 3715984 Fixed written prices Agreed before work starts, no hourly rates Boilers from £1,299 Fully fitted, immediate installation available FREE Gas Safety Certificate With every new boiler installation Open 7 days Mon–Sun, 8:30am–5:30pm Overview ## What This Service Is, and Who It Is For ### What it is A back boiler is a gas boiler built into the space behind a living room fireplace, usually feeding a gas fire on the front and the central heating system from behind, with the flue running up the original chimney breast. Back boiler replacement means disconnecting and removing that boiler, capping or removing the flue arrangement in the chimney, and fitting a modern boiler elsewhere in the house, most often a combi or system boiler in the kitchen, airing cupboard or loft. It is a bigger job than a straightforward like-for-like boiler swap because the old boiler's location, flue route and gas supply were designed around a fireplace that a modern boiler does not need. ### Who it is for Homeowners in older Merseyside terraces and semis where the original gas fire and back boiler have never been replaced, anyone whose living room fireplace is boxed in around an ageing boiler they cannot get serviced or parts for, and buyers of period property who have found a back boiler during survey and need it dealt with before it fails completely. ### When you need it Most back boilers still in service are decades old, well past the point where manufacturers support them with spares, and many are running at efficiencies that a modern condensing boiler comfortably beats. If yours is struggling to heat the house, has failed a service, or you simply want the fireplace and chimney breast back for something other than housing a boiler, replacement is worth planning for rather than waiting on a breakdown in winter. ### Why it needs a registered engineer Parts for back boilers are increasingly hard to source, so a fault that would be a same-day repair on a modern boiler can leave a back boiler beyond economical repair. They also tend to be far less efficient than a current condensing combi or system boiler, so a household is often paying more in gas for less heat. Removing one properly, rather than just disconnecting it and leaving it behind the fireplace, also means dealing with the flue and chimney correctly so the space is safe to close up or reuse. Related services - Boiler Installation - Combi Boiler Installation - Heating System Upgrades - New Boiler Cost Guide Areas we cover - Liverpool - Knowsley - Prescot - Halton - St HelensTowns we cover West Derby, Belle Vale & Netherley, Clock Face & Sutton Manor, Tarbock Green, Hough Green, Huyton, Kirkby, Halewood, Whiston, Rainhill, Eccleston Park, Newton-le-Willows, Widnes, Runcorn, Woolton, Allerton, Childwall, Wavertree, Garston, Speke, Crosby, Bootle, Aintree, Maghull, Birkenhead Speak to an engineer Mon–Sun, 8:30am–5:30pm 07523 738285Get a Free Quote The cost of leaving it ## What Happens If This Gets Left A back boiler that has quietly done its job for thirty years does not fail gently, and the removal is not as simple as unbolting a box. ### Risks and escalating costs - When a back boiler finally fails beyond repair, it is usually in the coldest part of the year, and sourcing replacement parts can take longer than most households can go without heating. - Leaving an old back boiler disconnected but still sitting in the chimney breast, rather than removed and the flue properly capped, is not a safe long-term arrangement and can cause problems if the fireplace is later opened up or used again. - An unlined or poorly lined chimney that has carried a back boiler flue for decades often needs attention before it can be reused for anything else, or before it can be safely sealed. - Old gas supply pipework sized for a back boiler and gas fire together is not always adequate for a modern high-output combi, and undersized supply pipework causes pressure problems that show up as soon as the new boiler is put under load. - Skipping a proper system flush when converting from an old back boiler means decades of sludge and debris in the pipework and radiators gets pushed straight into the new boiler's heat exchanger, which is exactly what most manufacturers check for before honouring a warranty claim. ### Mistakes we are called out to fix - Having the old boiler disconnected and left in place rather than fully removed, which leaves the chimney breast unusable and the flue arrangement unresolved. - Assuming the existing gas meter and supply pipework will automatically cope with a modern combi's higher gas rate without it being checked. - Choosing a new boiler location without checking there is a suitable route for the flue, the condensate drain and the gas and water connections. - Not budgeting for making good the fireplace opening and chimney breast, which is a separate job from the heating work itself. - Skipping a full system flush after decades of sludge build-up behind the old back boiler, then wondering why the new boiler is noisy or underperforming within months. Our process ## How We Carry Out the Work, Step by Step - 1 ### Step 1: Survey and conversion plan We inspect the existing back boiler, the flue route up the chimney, the gas meter and supply pipework, and the rooms available for the new boiler's location. We also look at the fireplace opening and chimney breast to establish what making good will involve once the old boiler is out. - 2 ### Step 2: Written specification and fixed price You get the plan in writing: new boiler make and model, whether it is a combi or system boiler, the flue route and boiler location, any gas supply upgrade needed, the tank and cylinder removal if applicable, the making good allowance for the fireplace, and the total price before any work starts. - 3 ### Step 3: Isolation and back boiler removal Gas and water are isolated, the old back boiler is disconnected and removed from behind the fireplace, and the redundant flue is capped or removed from the chimney in line with current regulations. Where the gas fire is being kept or removed, we deal with that connection at the same time. - 4 ### Step 4: New boiler installation and gas supply check The new combi or system boiler is fitted in its agreed location with a compliant flue and condensate route. We check the incoming gas supply and meter against the new boiler's gas rate, and upgrade the supply pipework where the survey identified it as undersized. - 5 ### Step 5: Tank, cylinder and pipework work Where converting to a combi, redundant cold water tanks and the hot water cylinder are drained, disconnected and removed, and feed and expansion pipework no longer needed is capped off properly. The system is then flushed to clear decades of accumulated sludge before the new boiler is connected. - 6 ### Step 6: Commission, certify and make good The new boiler is commissioned, combustion readings taken and recorded, and the system dosed with inhibitor and protected with a magnetic filter. We hand over the Benchmark commissioning record and your free Gas Safety Certificate, and leave the fireplace opening made good and ready for you to finish or fit a surround. What you get ## The Difference It Makes ### Fireplace and chimney breast reclaimed Once the old back boiler and flue are properly removed and the chimney capped, the fireplace opening is genuinely free for a new fire, a feature, or simply plastering over. ### A boiler that can actually be serviced and repaired Modern combi and system boilers from brands still fully supported with parts, rather than a back boiler where a failed component can mean weeks waiting on a hard-to-source part. ### Gas supply checked, not assumed We measure the existing supply against the new boiler's gas rate and upgrade pipework where needed, rather than fitting a new boiler onto a supply that was only ever sized for the old one. ### System flushed before the new boiler sees it Decades of sludge from behind an old back boiler are cleared out with a proper flush, protecting the new boiler's heat exchanger rather than passing the problem straight into it. ### Tanks and cylinder out where you convert to combi Loft tanks and the airing cupboard cylinder are removed as part of the job, giving you that storage space back rather than leaving redundant pipework and tanks in place. ### Fixed written price covering the whole conversion One price for removal, the new boiler, gas supply work, tank and cylinder removal and making good, agreed before we start rather than a series of separate quotes as the job progresses. In detail ## Converting from a Back Boiler in Detail Back boilers were fitted in huge numbers across Liverpool and Merseyside terraces from the 1960s through to the 1980s, almost always tucked behind a gas fire in the living room chimney breast. The arrangement made sense at the time: one flue serving both the fire and the boiler, and the boiler hidden out of sight. Decades on, that same arrangement is usually the reason a household is stuck with an inefficient boiler in an awkward spot, because the boiler cannot be replaced like-for-like without either sourcing an increasingly rare direct replacement or converting the whole arrangement to a modern boiler in a different location. Removing the old unit is only the first part of the job. The flue that served the back boiler runs up the original chimney, and once the boiler is gone that flue needs to be properly capped, or the chimney needs lining and finishing if it is going to be reused for a gas fire or left open. We check the condition of the chimney breast and flue as part of the survey, because a chimney that has carried a boiler flue for forty years is not always in a state to simply seal up without some remedial work first. Where the gas fire connected to the back boiler is being kept, we deal with that connection separately from the boiler conversion, either capping it off safely if the fire is being removed too or maintaining a compliant supply if it is staying. Where the fire is removed along with the boiler, the fireplace opening is left ready for you to finish with plastering, a surround, or simply boarding over, since that finishing work is a building job rather than a gas and heating one. Converting to a combi boiler usually means removing the cold water storage tanks in the loft and the hot water cylinder in the airing cupboard, since a combi heats water on demand from the mains rather than storing it. This gives back loft space and, more usefully in many Merseyside terraces, a full airing cupboard that has been occupied by a cylinder for decades. Where mains pressure or flow rate does not comfortably support a combi, or where the household regularly needs hot water in two places at once, a system boiler with an unvented cylinder is often the better fit, keeping stored hot water but at mains pressure rather than the old low-pressure gravity-fed arrangement a back boiler typically ran. The gas supply itself needs checking rather than assuming, because a back boiler running alongside a gas fire was sized for that combined demand, and a modern combi boiler often has a higher instantaneous gas rate than the old back boiler alone. We check the meter, the supply pipe diameter and the route from meter to boiler, and where it falls short we upgrade the pipework as part of the job rather than fitting a new boiler that cannot draw the gas it needs under full load. ### Residential and commercial properties Back boiler removal is overwhelmingly a job we see in older Merseyside terraces and inter-war semis, where the original chimney breast, narrow hallways and period fireplace all shape what is practical. Terraces often have limited space for a new boiler location, so we look at kitchens, understairs cupboards and lofts as alternatives during the survey. Where a property has already had partial work done, such as a gas fire replaced without the back boiler being touched, we check exactly what is connected to what before quoting, since previous work is not always documented. ### Variations of this service - Back boiler to combi conversion Full removal of the old boiler, flue and gas fire arrangement, tank and cylinder removal, and installation of a combi boiler in a new location such as the kitchen or airing cupboard. - Back boiler to system boiler conversion Removal of the old back boiler and installation of a system boiler paired with an unvented cylinder, kept for households with higher hot water demand or lower mains flow. - Chimney and flue making good Capping or removing the redundant flue, assessing chimney condition, and leaving the chimney breast in a safe state whether it is being reused or sealed. - Fireplace opening and gas fire handling Safely capping off or maintaining the gas fire supply depending on whether the fire is kept or removed alongside the boiler conversion. - Full system flush and pipework check Clearing accumulated sludge from decades of service and checking existing pipework and radiators are fit to run on a modern condensing boiler. ### Materials, parts and equipment - Worcester Bosch, Vaillant, Baxi and Heatline combi and system boilers - Flue components and chimney capping suited to the specific property - Unvented hot water cylinders for system boiler conversions - Copper and press-fit pipework with full-bore isolation valves - Magnetic system filter and central heating inhibitor - Upgraded gas supply pipework where the survey identifies it as undersized Questions ## Back Boiler Removal & Replacement: Frequently Asked Questions What is a back boiler and how do I know if I have one?A back boiler is a gas boiler fitted behind a living room fireplace, usually alongside a gas fire, with the flue running up the chimney. If your boiler is not a wall-mounted box in the kitchen, airing cupboard or loft, and your fireplace has a boiler control or gauge visible near it, you very likely have a back boiler. Can a back boiler be replaced with another back boiler?Direct back boiler replacements are increasingly hard to source and are not something we fit. In practice, replacement means converting to a modern combi or system boiler installed elsewhere in the property, which is a more reliable long-term solution. What happens to my fireplace once the back boiler is removed?The old boiler and its flue arrangement are removed and the chimney is capped or made safe. The fireplace opening is left ready for you to finish, whether that is plastering over, boarding, or fitting a surround, since that decorative finishing is separate from the heating work. Do I need to keep my gas fire if I remove the back boiler?No. If you want to keep the gas fire we maintain a compliant supply to it separately from the boiler conversion. If you are removing the fire as well, we cap the gas supply to it safely as part of the same job. Will my chimney need work once the back boiler flue is removed?It depends on its condition. Some chimneys can simply be capped once the flue is out, others need lining or remedial work if they are going to be reused or if the survey shows the brickwork has been affected by decades of flue gases. We check this during the survey and tell you before quoting. Should I convert to a combi or a system boiler?It depends on your hot water demand and mains water pressure and flow. A combi suits most single-bathroom households and frees up the airing cupboard and loft. A system boiler with a cylinder suits homes needing hot water in two places at once, or with lower mains flow. We measure your supply and talk through both options before recommending one. How long does a back boiler conversion take?It is a larger job than a like-for-like boiler swap because of the flue, chimney and tank and cylinder work involved, so it typically takes longer than a straightforward boiler replacement. We give you an expected number of days in the written quote once we have surveyed the property. How much does back boiler replacement cost?It depends on the conversion involved: whether tanks and a cylinder need removing, whether the gas supply needs upgrading, and how much making good the fireplace needs. New boilers are fully fitted from £1,299 with a free Gas Safety Certificate, and we confirm the full conversion price in writing before work starts. Do you cover back boiler removal across Merseyside?Yes, across Liverpool, Knowsley, Halton and St Helens, where this kind of older terrace and semi housing is common. We answer the phone seven days a week, 8:30am to 5:30pm, on 07523 738285 or 0151 384 5908. Still not sure? Send us the details or ring 07523 738285. Your next step ## Get Your Fixed Price in Writing Send us the details and we'll come back with a clear price, or ring now if you're without heating or hot water. - Gas Safe registered no. 576059 · licence no. 3715984 - 25 Bardley Cres, Tarbock Green, Liverpool L35 1RJ - 07523 738285 · 0151 384 5908 - info@harrisonejonesheating.co.uk - Mon–Sun, 8:30am–5:30pmCall 07523 738285 ### Request your free fixed price Takes under a minute. No pushy sales visit, no obligation. Or call us direct on 07523 738285 · 0151 384 5908 Gas Safe registered heating and boiler engineers serving Liverpool, Knowsley, Halton, St Helens and the wider Merseyside area. 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