The Baxi
400.
A 24kW combi boiler from Baxi — installed in a single day by Gas Safe registered engineers.
Built for real homes.
Not showrooms.
The Baxi 400 24kW is designed to work quietly, efficiently, and reliably — for years to come.
- Compact cupboard-fit design
- Quiet operation
- Durable brass hydraulics and stainless steel heat exchanger
- 24kW heat output — Combi boiler
- 21kW central heating output
- 10.2 L/min hot water flow rate
- 5 year manufacturer warranty
- 93% 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 400 24kW
The Baxi 400 24kW is Baxi's entry-level combi, built for homes where reliable heating and instant hot water matter more than bells and whistles. Compact, lightweight, and exceptionally quiet, it can be installed virtually anywhere in your home — including inside a standard kitchen cupboard.
A stainless steel heat exchanger and brass hydraulics keep things durable under the hood, while A-rated efficiency means it won't cost you more to run than it needs to. The external pressure gauge lets you top up the system yourself without calling an engineer, and it's compatible with the Baxi uSense smart thermostat for app-controlled heating.
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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