The heating professional should assess the property, radiators, pipework, water pressure, hot-water demand and heating controls before recommending the final boiler.

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APN Boilers helps homeowners find experienced heating professionals who can assess the complete system and recommend an appropriate Baxi boiler installation.

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Is a Baxi Boiler Suitable for Your Home?

 

Baxi currently offers combi, system, heat-only and electric boilers. Its ranges include models suitable for domestic natural gas, LPG and electric heating installations.

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A Baxi boiler may be suitable where a homeowner wants:

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• A compact combi boiler

• A boiler capable of fitting inside a kitchen cupboard

• A replacement for an existing combi boiler

• A system boiler connected to a hot-water cylinder

• A heat-only boiler for a traditional system

• A choice of different outputs and warranty periods

• Smart or programmable heating controls

• Natural gas or selected LPG options

• A magnetic system filter included with certain models

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The boiler brand is only one part of a successful installation. Correct sizing, system cleaning, control selection and commissioning will have a major effect on performance and reliability.

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Baxi Combi Boilers

 

A Baxi combi boiler provides central heating and instantaneous hot water from one appliance.

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It normally removes the need for a separate hot-water cylinder or cold-water storage tanks, making it a practical option where space is limited.

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Baxi describes combi boilers as particularly suitable for homes with one bathroom. The manufacturer also notes that hot-water flow can reduce when more than one hot tap is operated simultaneously.

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A Baxi combi boiler may suit:

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• Flats and apartments

• Smaller houses

• Medium-sized family homes

• Properties with one main bathroom

• Homes already using a combi boiler

• Properties where tanks and cylinders are being removed

• Projects where cupboard installation is important

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The final model should be selected using the property’s heating load and hot-water requirements, rather than bedroom numbers alone.

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Check the Water Flow Before Choosing a Baxi Combi Boiler

 

A larger combi boiler does not create a better incoming water supply.

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The boiler can only heat and deliver the quantity of water reaching the property. A powerful combi connected to a restricted water main may still produce disappointing shower and bath performance.

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Before recommending a Baxi combi boiler, the installer should test:

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• Static mains-water pressure

• Dynamic pressure while an outlet is running

• Incoming flow rate

• Diameter of the incoming water main

• Condition of the internal water pipes

• Number of bathrooms

• Number of showers

• Likelihood of simultaneous hot-water use

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A combi may work extremely well in a home with one bathroom and a strong mains supply. A system boiler and storage cylinder may provide a better result where several bathrooms or outlets are used at the same time.

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The Baxi Combi Boiler Range

 

The Baxi combi boiler range includes products at different specifications and warranty levels.

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Current ranges include:

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• Baxi 400 Combi 2.1

• Baxi 600 Combi 2

• Baxi 800 Combi 2

• Baxi Platinum Compact Combi

• Baxi Duo-tec Compact Combi

• Baxi MainEco Compact Combi

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The precise models, outputs and availability can change, so the selected appliance should be checked against current manufacturer information before installation.

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Baxi 400 Combi 2.1

 

The Baxi 400 Combi 2.1 is a compact and lightweight combi boiler positioned towards the accessible end of the Baxi range.

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Current models include a five-year parts and labour warranty, with 24kW and 30kW LPG versions available for properties without mains gas.

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The Baxi 400 may be considered for:

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• Flats and smaller houses

• Straightforward combi replacements

• Properties with modest hot-water demand

• Landlords seeking a compact replacement boiler

• Homes requiring an LPG-compatible model

• Projects where installation space is restricted

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A 24kW or 30kW label should not be used as the only basis for selection. The installer must still consider heat loss, radiator load and water flow.

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Baxi 600 Combi 2

 

The Baxi 600 Combi 2 is a compact mid-range combi boiler with a seven-year parts and labour warranty.

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The current range is compatible with the Baxi uSense 2 smart thermostat and includes Baxi’s EasyFill feature for topping up the central-heating system pressure.

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The range includes 24kW, 30kW and 36kW models.

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A Baxi 600 Combi 2 may suit homeowners looking for:

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• A compact replacement boiler

• A choice of domestic hot-water outputs

• Smart-control compatibility

• A longer warranty than an entry-level model

• A cupboard-sized appliance

• Natural gas or selected LPG installation

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The higher-output models can provide stronger instantaneous hot-water performance, provided the incoming mains supply is capable of delivering the required flow.

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Baxi 800 Combi 2

 

The Baxi 800 Combi 2 sits towards the higher-specification end of the numbered Baxi range.

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It currently includes:

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• A ten-year parts and labour warranty

• An Adey MagnaClean Micro2 magnetic system filter

• EasyFill pressure top-up

• A pre-heated condensate trap intended to reduce the risk of freezing in winter

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The magnetic filter forms an important part of the warranty package. Baxi states that the filter must be fitted and maintained for the full warranty period; otherwise, the warranty may revert to two years.

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The Baxi 800 may be considered where the homeowner wants:

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• A ten-year warranty

• A system filter included with the boiler

• A higher-specification Baxi combi

• Simple pressure top-up

• Smart heating-control options

• A boiler suitable for a longer-term installation

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The system should still be cleaned before installation. A new magnetic filter will help capture circulating debris, but it is not a substitute for dealing with heavily contaminated system water.

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Baxi Platinum Compact Combi

 

The Baxi Platinum Compact Combi is a higher-specification compact boiler available in 25kW, 30kW and 36kW models.

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It currently offers:

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• A ten-year parts and labour warranty

• An Adey Micro2 magnetic filter

• EasyFill pressure top-up

• Compatibility with the Baxi uSense smart thermostat

• Cupboard-compatible dimensions

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This range may appeal to homeowners looking for:

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• A premium Baxi combi boiler

• A long manufacturer warranty

• A compact installation

• Several hot-water output options

• Smart-phone heating control

• A filter included as part of the boiler package

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The 36kW model should not automatically be chosen because it is the most powerful. The installer should confirm that the property has sufficient mains-water flow and that the boiler can operate effectively against the building’s space-heating requirement.

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Baxi Duo-tec Compact Combi

 

The Baxi Duo-tec Compact Combi is available in 25kW, 30kW and 36kW models and currently carries a seven-year parts and labour warranty.

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The appliance is designed to fit into a 290mm-deep kitchen cupboard and is compatible with the Baxi uSense 2 smart thermostat.

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It may be considered where:

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• The boiler must fit into a kitchen cupboard

• A straightforward combi replacement is required

• The homeowner wants brass hydraulic components

• Smart heating control is required

• Several hot-water outputs need to be compared

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The cupboard must still provide the clearances and servicing access required by the manufacturer.

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Baxi MainEco Compact Combi

 

The Baxi MainEco Compact Combi is a lightweight, cupboard-sized combi boiler with a five-year warranty and compatibility with Baxi OpenTherm controls.

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It may suit:

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• Smaller homes

• Rental properties

• Straightforward boiler replacements

• Installations with a limited budget

• Properties with one main bathroom

• Projects requiring a compact appliance

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Homeowners should confirm whether the quote is for a Baxi-branded model or a boiler within the wider Baxi Heating group, as the group includes several heating brands.

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Baxi System Boilers

 

A Baxi system boiler heats the radiators and works with a separate hot-water cylinder.

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Unlike a combi boiler, the cylinder stores heated water for later use. This can make a system boiler more appropriate for larger homes or properties where several people may require hot water at similar times.

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Baxi system boilers are compatible with unvented cylinders, including Baxi cylinders and the Megaflo Eco range.

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A Baxi system boiler may be suitable for:

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• Larger houses

• Properties with two or more bathrooms

• Homes with an existing unvented cylinder

• Households using several showers

• Properties with greater hot-water demand

• Heating systems divided into several zones

• Homes where stored hot water is preferred

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The boiler and cylinder must be designed together. Installing a powerful boiler with an undersized cylinder will not provide the required hot-water capacity.

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Baxi 800 System 2

 

The Baxi 800 System 2 is designed to work with a hot-water cylinder and is positioned for homes requiring larger quantities of stored hot water.

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The current model includes:

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• A ten-year parts and labour warranty

• An Adey Micro2 magnetic system filter

• Compatibility with the Baxi uSense smart thermostat

• Natural gas and LPG operation without a conversion kit

• A pre-heated condensate trap

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Baxi specifically identifies the 800 System 2 as a solution for properties with more than one bathroom or greater hot-water requirements.

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The installer should also assess:

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• Cylinder capacity

• Cylinder recovery time

• Incoming water pressure

• Expansion arrangements

• Motorised valves

• Heating zones

• Cylinder thermostat

• Hot-water programming

• Pipe sizes

• System-water condition

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Baxi Heat-Only Boilers

 

Heat-only boilers are also described as regular, conventional or open-vent boilers.

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They normally work with a separate hot-water cylinder. Traditional installations may also have cold-water storage and feed-and-expansion tanks in the roof space.

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A Baxi heat-only boiler can be suitable where:

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• The existing system is being retained

• The property already has a suitable cylinder

• The existing pipework is designed for an open-vented system

• The incoming mains supply is unsuitable for a combi

• Several hot-water outlets may be used

• The homeowner wants to minimise alterations

• A direct replacement is more practical than a system conversion

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Baxi states that its heat-only boilers are available in several outputs and can be used with Baxi cylinders and Megaflo Eco products.

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Baxi 800 Heat

 

The Baxi 800 Heat is a compact heat-only boiler supplied with a magnetic system filter and a ten-year parts and labour warranty.

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It can fit inside a standard kitchen cupboard and offers a rear-flue option for certain installations. It is also compatible with the Megaflo Eco cylinder range.

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The ten-year warranty requires the supplied magnetic filter to be installed, registered and maintained in accordance with Baxi’s conditions.

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This model may be relevant for:

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• Traditional heating-system replacements

• Larger houses

• Properties retaining a hot-water cylinder

• Homes with several bathrooms

• Cupboard installations

• Projects requiring a compact heat-only appliance

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Replacing like-for-like may reduce disruption, but the installer should still inspect the tanks, cylinder, controls, valves and pipework.

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Baxi Boiler Prices

 

Baxi boiler prices vary according to the boiler type, output, specification, controls, warranty and supplier.

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Current consumer price guides place standalone Baxi combi boilers at approximately £730 to £1,300, excluding installation, flue components, controls and other materials.

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Another current market guide estimates that a typical new Baxi boiler installation may cost approximately £2,000 to £2,600, although conversions, relocations and major system alterations can increase this substantially.

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The following figures are broad homeowner guides rather than fixed quotations.

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Baxi boiler installation   /   Indicative installed cost

Straight forward Baxi combi replacement £2,000–£3,000

Baxi 600 or Duo-tec combi £2,300–£3,500

Baxi 800 or Platinum combi £2,600–£4,000

Baxi system-boiler replacement £2,400–£4,000

Baxi heat-only replacement £2,300–£3,800

Boiler relocation £3,500–£5,500+

Traditional system converted to combi £3,500–£6,000+

New system boiler and cylinder £4,000–£7,000+

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A national replacement service currently advertises like-for-like combi installations from £1,790 and standard-to-combi conversions from £2,690. These starting figures illustrate the difference between a simple replacement and a change of heating-system type.

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What Affects Baxi Boiler Costs?

 

The boiler unit may represent only part of the total installation cost.

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Baxi boiler costs can be affected by:

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• Boiler model

• Boiler output

• Warranty package

• Combi, system or heat-only arrangement

• Existing boiler position

• Proposed new boiler position

• Flue length and direction

• Roof or high-level flue access

• Scaffolding

• Gas-pipe size

• Condensate drainage

• Electrical work

• Heating controls

• Magnetic system filter

• System cleaning

• Chemical inhibitor

• Radiator replacement

• Heating zones

• Tank and cylinder removal

• New unvented cylinder

• Floor and wall access

• Making good and decoration

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An advertised boiler price may apply only to a straightforward appliance replacement in the same position.

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The written quotation should explain whether the price includes the flue, controls, filter, system cleaning, certification and disposal of the old appliance.

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Baxi Boiler Replacement

 

A Baxi boiler replacement may be relatively straightforward where the new boiler remains in the same location and the existing heating-system type is retained.

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However, the installer should not assume that every component connected to the old boiler remains suitable.

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The pre-installation assessment should include:

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• Existing boiler type

• Boiler location

• Flue route

• Gas supply

• Condensate drainage

• Heating flow and return pipes

• Radiators

• Thermostatic radiator valves

• Hot-water cylinder

• Storage tanks

• Expansion arrangements

• Electrical supply

• Heating controls

• System-water condition

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A new boiler connected to restricted, dirty or poorly balanced pipework may not deliver the expected improvement.

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Converting to a Baxi Combi Boiler

 

Many homeowners want to replace an older heat-only boiler and remove the hot-water cylinder and roof tanks.

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A Baxi combi conversion can release storage space and simplify the heating arrangement, but it involves more work than a straightforward boiler swap.

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The conversion may require:

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• Removal of the existing boiler

• Disconnection of the cylinder

• Removal or abandonment of roof tanks

• New hot and cold-water pipes

• Heating flow-and-return alterations

• Upgraded gas pipework

• New condensate drainage

• A revised flue position

• Electrical alterations

• New heating controls

• System cleaning

• Making good

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The incoming water supply must be tested before the conversion is agreed.

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A high-output Baxi combi will not compensate for poor water pressure or a restricted water main. Where the property has several bathrooms, retaining stored hot water may provide a better result.

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Choosing the Correct Baxi Boiler Size

 

The correct Baxi boiler cannot be selected accurately by counting bedrooms alone.

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The installer should consider:

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• Property dimensions

• Construction type

• Insulation

• Wall, floor and roof heat loss

• Window sizes

• Type of glazing

• Radiator sizes

• Underfloor heating

• Number of bathrooms

• Incoming water flow

• Household hot-water habits

• Planned extensions or loft conversions

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Combi boiler outputs are frequently driven by instantaneous hot-water requirements rather than the property’s space-heating load.

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A property may only require a relatively modest output for heating but need a 30kW or 36kW combi to achieve the desired hot-water flow.

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The boiler must therefore be capable of reducing its output when the heating demand is low. Correct commissioning and control selection are particularly important.

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Baxi Heating Controls

 

Modern controls allow the heating system to respond more closely to the household’s requirements.

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Depending on the selected boiler, the installation could include:

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• Programmable room thermostat

• Wireless thermostat

• Smart-phone control

• Baxi uSense thermostat

• OpenTherm control

• Weather compensation

• Load compensation

• Thermostatic radiator valves

• Separate heating zones

• Hot-water scheduling

• Underfloor-heating controls

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Current Baxi 600, 800, Platinum and Duo-tec products include compatibility with Baxi smart-control options, although accessories and gateways may be required for some installations.

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The controls should be considered at the design stage rather than selected after the boiler has been installed.

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A larger property may benefit from separate heating zones for different floors or areas. This prevents the entire house being heated whenever only one part is occupied.

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Baxi Boiler Warranties

 

Baxi warranties vary according to the boiler range.

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Baxi currently states:

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• Baxi 800 boilers: ten-year parts and labour warranty

• Baxi 600 boilers: seven-year parts and labour warranty

• Baxi 400 boilers: five-year parts and labour warranty

• Baxi 200 boilers: two-year parts and labour warranty

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The warranty normally requires:

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• Registration within 30 days

• Completion of the Benchmark Commissioning Checklist

• Annual boiler servicing

• Installation and maintenance of the required magnetic filter where applicable

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Failure to meet these requirements may cause the warranty to revert to the standard one-year period.

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Homeowners should ask the installer to confirm:

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• Exact warranty period

• Who will register the boiler

• Whether a magnetic filter is required

• Who will complete the Benchmark documentation

• Annual servicing requirements

• Which records must be retained

• Who should be contacted in the event of a fault

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The quotation should state the actual warranty applying to the selected boiler, not simply advertise a warranty of “up to ten years.”

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Gas Safe Baxi Boiler Installation

 

A Baxi gas boiler must be installed by a suitably qualified Gas Safe registered engineer.

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The installer should also be qualified for the relevant type of gas, appliance and installation work.

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Following installation, the homeowner should normally receive:

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• Completed Benchmark documentation

• Building Regulations compliance certificate

• Baxi warranty confirmation

• Boiler instructions

• Heating-control instructions

• Service requirements

• Itemised invoice

• Relevant electrical certification

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These documents should be retained with the property records.

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What Should a Baxi Boiler Quote Include?

 

A proper Baxi boiler quotation should identify:

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• Exact Baxi range

• Exact model

• Boiler output

• Boiler type

• Proposed location

• Flue arrangement

• Heating controls

• Magnetic system filter

• System cleaning

• Chemical inhibitor

• Gas-pipe alterations

• Condensate drainage

• Electrical work

• Removal of the existing boiler

• Tank or cylinder removal

• Making good

• Warranty period

• Commissioning

• Certification

• VAT

• Exclusions

• Potential additional costs

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This makes it easier to compare quotations on a like-for-like basis.

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A lower quotation may exclude the filter, controls, flushing, electrical work or making good. The cheapest initial quote may not represent the lowest final cost.

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Find a Baxi Boiler Installer Through APN Boilers

 

APN Boilers is being developed as a nationwide resource for boiler installation, replacement boilers and heating-system improvement.

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The network is supported by more than 40 years of experience in residential property, construction and home improvement.

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We understand that replacing a boiler is not simply a matter of installing a new appliance.

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The heating professional may need to assess:

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• Property heat loss

• Radiator output

• Heating flow and return pipes

• Water pressure and flow

• Hot-water demand

• Gas-pipe capacity

• Flue position

• Cylinder requirements

• Heating zones

• Smart controls

• Future property improvements

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Through APN Boilers, homeowners can request contact from suitable independent heating professionals covering their area.

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Tell Us About Your Baxi Boiler Project

 

To help the installer understand the project, tell APN Boilers:

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• Property location

• Existing boiler make and model

• Existing boiler type

• Whether the property has tanks or a cylinder

• Number of bedrooms

• Number of bathrooms

• Approximate number of radiators

• Whether the boiler will remain in the same position

• Preferred Baxi model, where known

• Whether controls need upgrading

• Whether radiators need replacing

• When the work is required

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This information helps the heating professional provide a more appropriate recommendation and quotation.

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Frequently Asked Questions

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Are Baxi boilers good boilers?

Baxi offers combi, system and heat-only boilers across several specifications and warranty levels. The completed system’s performance will also depend on correct selection, installation, controls, cleaning and commissioning.

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How much is a Baxi combi boiler?

A standalone Baxi combi boiler may cost approximately £730 to £1,300. A straightforward installed replacement will commonly cost approximately £2,000 to £4,000, depending on the model and work required.

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Which Baxi combi boiler do I need?

The correct model depends on the property’s heat loss, available water flow, hot-water demand, number of bathrooms, boiler location and required warranty.

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What is the difference between the Baxi 600 and Baxi 800?

The Baxi 600 currently has a seven-year warranty, while the Baxi 800 has a ten-year warranty and includes a magnetic system filter. The exact specification should be checked for the selected model.

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Can a Baxi combi boiler supply two showers?

A combi may supply substantial hot-water demand where the boiler output and incoming mains flow are sufficient. A system boiler and cylinder may provide a better result where several outlets are regularly used together.

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Are Baxi system boilers suitable for larger houses?

Baxi system boilers can be suitable for larger homes, particularly where there are several bathrooms or greater stored hot-water requirements. The boiler and cylinder must both be sized correctly.

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Can I replace a heat-only boiler with a Baxi combi?

This is often possible, but the water pressure, flow rate, gas supply, pipework and household hot-water requirements must be assessed before the cylinder and tanks are removed.

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How long is a Baxi boiler warranty?

Current Baxi boiler warranties generally range from two to ten years, depending on the range and compliance with the manufacturer’s registration, commissioning and servicing requirements.

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Does a Baxi boiler need annual servicing?

Annual servicing is required to maintain the manufacturer’s extended warranty and allows the appliance and safety components to be inspected.

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Who can install a Baxi gas boiler?

A Baxi gas boiler must be installed and commissioned by a suitably qualified Gas Safe registered engineer.

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Find the Right Baxi Boiler for Your Home

 

Choosing the right Baxi boiler starts with understanding the property, the existing heating system and the amount of heating and hot water your household needs. APN Boilers can connect you with experienced local heating professionals who can assess the installation, recommend a suitable Baxi boiler and provide a clear quotation for the work. Tell us about your property and what you would like to achieve, and we will help you take the next step.