Baxi
800 18kW System
A 18kW system boiler from Baxi — installed in a single day by Gas Safe registered engineers.
Built for real homes.
Not showrooms.
The Baxi 800 18kW is designed to work quietly, efficiently, and reliably — for years to come.
- Adey Micro2 magnetic system filter included
- Works with Baxi and Megaflo Eco cylinders
- Pre-heated condensate trap to help prevent freezing
- External pressure gauge for easy top-ups
- Compatible with the Baxi uSense smart thermostat
- 18kW heat output — System boiler
- 18kW 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 quoteThe numbers
that matter.
Baxi 800 18kW
The Baxi 800 System 2 18kW is the top of Baxi's system boiler range. A system boiler works with a hot water cylinder, which suits homes that use a lot of hot water at once, and it works with cylinders such as the Baxi cylinder or Megaflo Eco.
It comes with an Adey Micro2 magnetic filter to protect the boiler from sludge in your heating system. A pre-heated condensate trap helps prevent freezing in winter, the external pressure gauge makes top-ups easy, and it works with the Baxi uSense smart thermostat.
Backed by a 10-year Baxi parts and labour warranty. Baxi requires the Adey filter to stay fitted for the full warranty, so have it cleaned at each annual service.
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, subject to status.
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