System boiler

The Baxi
800.

A 24kW system boiler from Baxi — installed in a single day by Gas Safe registered engineers.

Fully installed from
£2,900
Finance available
24kWHeat output
SystemBoiler type
10 yearsManufacturer warranty
1–2 dayInstallation
Baxi 800 Sytem Boiler
System boiler
24kW output

Built for real homes.
Not showrooms.

The Baxi 800 24kW is designed to work quietly, efficiently, and reliably — for years to come.

  • Brass Hydraulics
  • Compact Design
  • 24kW heat output — System boiler
  • 24kW central heating output
  • 10 year manufacturer warranty
  • 94% ErP efficiency rating

One price.
Everything covered.

No surprise add-ons. Your quote covers everything needed for a complete installation that meets all gas safety regulations, carried out by Gas Safe registered engineers.

Price and installation time varies depending on your installation requirements. Answer a few quick questions to get your exact fixed price.

Get your free quote
Flue, fittings & full installation
Magnetic system filter
System cleanse & inhibitor
Removal & safe disposal of your old boiler
Gas Safe registered installation certificate
Warranty registration

The numbers
that matter.

Boiler type
System
System type
Heat output
24kW
System boiler
Central heating
24kW
Heating output
Efficiency
94%
ErP energy rating
Warranty
10 years
Manufacturer guarantee
Dimensions
H 700 x W 395 x D 285 mm
Width × height × depth
Fully installed from
£2,900
Fully installed, no extras

Baxi 800 24kW

The Baxi 800 System 2 is the top-tier system boiler in the Baxi range, designed for larger homes where consistent hot water to multiple bathrooms is the priority. With all heating components built in and a separate cylinder handling hot water storage, it delivers steady pressure and reliable performance throughout the home.

A built-in Adey MagnaClean Micro2 filter protects the system from day one, and brass hydraulics throughout add durability for the long term. Compatible with Baxi uSense smart controls, quiet in operation, and simple to service thanks to front-access design.

Backed by a 10-year parts and labour warranty.

Don't let cost get
in the way of warmth.

Spread the cost of your new boiler over monthly payments that fit your budget. Available through iDeal4Finance — apply in minutes.

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Representative example only. Subject to status. Boxheat Ltd is an Introducer Appointed Representative of Ideal Sales Solutions Ltd t/a Ideal4Finance (FN 703047).