If you’re looking for a reliable, efficient, and installer-friendly combi boiler, the Baxi 800 Combi 2 is one of the strongest options currently available on the UK market. At Challenger Heating Services, we’ve installed many of these boilers across Sutton Coldfield, Lichfield, Tamworth, Walsall and Birmingham, and it continues to be a boiler we confidently recommend to our customers.

In this review, we’ll look at the key features, benefits, outputs, and why the Baxi 800 Combi 2 has become one of our favourite boilers to install.

Our Overall Verdict

The Baxi 800 Combi 2 is an excellent mid-to-premium range combi boiler that offers fantastic value for money. It combines high efficiency, a long warranty, quality components, flexible installation options, and excellent manufacturer support.

For homeowners looking for a dependable boiler without spending top-end prices, the Baxi 800 Combi 2 is definitely worth considering.

Rating: 9/10

10-Year Manufacturer’s Warranty

One of the biggest selling points of the Baxi 800 Combi 2 is its impressive 10-year manufacturer’s warranty, subject to annual servicing and compliance with the manufacturer’s terms.

In our experience, Baxi’s warranty support is among the best in the industry. When customers experience a genuine warranty issue, Baxi are usually quick to respond and get the problem resolved without unnecessary delays.

This gives homeowners valuable peace of mind for the next decade.

Excellent Efficiency

The Baxi 800 Combi 2 is:

A-rated for central heating
A-rated for domestic hot water
Designed to help reduce energy consumption
Compatible with modern smart controls and weather compensation

Higher efficiency means lower running costs and reduced gas consumption compared to older boiler models.

Available in Three Outputs

Unlike some competing boilers, the Baxi 800 Combi 2 is available in three different outputs:

24kW Model

Hot water flow rate: 10.2 litres per minute
Ideal for smaller homes with one bathroom

30kW Model

Hot water flow rate: 12.2 litres per minute
Suitable for most average family homes

36kW Model

Hot water flow rate: 15 litres per minute
Perfect for homes with higher hot water demand

This gives homeowners more flexibility when selecting the correct boiler for their property.

For comparison, a Worcester Bosch Greenstar 4000 combi is available in 25kW and 30kW outputs, whereas the Baxi offers the additional 36kW option for larger hot water demands.

Stainless Steel Heat Exchanger

The Baxi 800 Combi 2 features a stainless steel heat exchanger.

Benefits include:

Excellent durability
Corrosion resistance
Long service life
Efficient heat transfer

Combined with brass hydraulic components, the boiler is built using quality materials designed to last.

Built-In Magnetic Filter

The boiler is supplied with a magnetic system filter in the box.

This helps:

Capture magnetite and sludge
Protect the heat exchanger
Improve reliability
Extend boiler lifespan

We still recommend maintaining clean system water and ensuring inhibitor levels are checked during annual servicing.

Easy-to-Use Pressure Gauge

Many modern boilers have removed the traditional pressure gauge and rely solely on digital displays.

The Baxi 800 Combi 2 still features a physical pressure gauge on the front of the boiler, making it easier for homeowners to quickly check system pressure without navigating digital menus.

It’s a small feature, but one many customers appreciate.

Internal Filling Loop

The Baxi includes a built-in filling loop as standard.

This means:

No separate braided filling loop is required
Easy pressure top-ups
Cleaner installation
Simple operation for homeowners

The blue filling lever located underneath the boiler makes repressurising the system straightforward.

Flexible Flue Options

The Baxi 800 Combi 2 offers a wide range of flue options including:

Standard horizontal flue
Left-hand flue installations
Right-hand flue installations
Vertical roof flue options
Long flue runs
Baxi Easy-Flue system

The Baxi Easy-Flue is particularly useful as it can often be installed from inside the property, reducing installation time and improving safety for engineers.

Compact Size

The Baxi 800 Combi 2 is surprisingly compact for a boiler with this level of performance.

Dimensions:

Height: 700mm
Width: 395mm
Depth: 285mm

The boiler can fit into cupboards as shallow as 290mm deep, making it ideal for kitchen cupboards and utility rooms.

For servicing, Baxi recommends approximately 450mm clearance in front of the boiler with the cupboard door open.

LPG Conversion Capability

Another excellent feature is that the Baxi 800 Combi 2 can be converted from Natural Gas to LPG.

This means:

No separate LPG model is required
Ideal for rural properties
Greater installation flexibility
Reduced stock requirements for installers

Installer-Friendly Design

As engineers, we appreciate the thought that has gone into the design of this boiler.

Features include:

Lightweight 29kg lift weight
Pipework can be run behind the boiler
Combined pressure relief valve and drain point
Excellent service access
Simple maintenance procedures

These design features reduce installation times and make future servicing and repairs easier.

Advanced Diagnostics

The latest Baxi interface provides engineers with extensive diagnostic information.

We can access:

Historical fault codes
Sensor readings
Operating parameters
Performance data

This significantly speeds up fault diagnosis and allows repairs to be completed more efficiently.

Smart Control Compatibility

The Baxi 800 Combi 2 works with:

Hive
Tado
Nest
ESI Controls
OpenTherm controls
Baxi controls
Weather compensation sensors

This allows homeowners to choose the control system that best suits their needs.

New AmbiZen Smart Controls

Baxi have recently expanded their range of wireless controls with the introduction of the AmbiZen Smart Control.

Features include:

Wireless installation
Smartphone control through the My Baxi App
Seven-day scheduling
Holiday mode
Energy monitoring
Weather compensation
Voice assistant compatibility
Google Assistant integration
Amazon Alexa integration

The system is designed to provide greater comfort while helping homeowners reduce energy consumption.

Who Is The Baxi 800 Combi 2 Suitable For?

The Baxi 800 Combi 2 is ideal for:

First-time boiler replacements
Growing families
Homes with one or two bathrooms
Customers wanting a 10-year warranty
Homeowners looking for excellent value for money
Customers wanting strong manufacturer support

Final Thoughts

The Baxi 800 Combi 2 combines everything most homeowners are looking for in a modern gas boiler: efficiency, reliability, flexibility and excellent warranty support.

The stainless steel heat exchanger, brass hydraulic components, built-in magnetic filter, OpenTherm compatibility and wide range of outputs make it a fantastic all-round package.

For many homeowners, it offers a genuine alternative to the Worcester Bosch Greenstar 4000 while often providing better value for money and the option of a larger 36kW output.

If you’re considering a new boiler installation in Sutton Coldfield, Lichfield, Tamworth, Walsall or Birmingham, we’d be happy to advise whether the Baxi 800 Combi 2 is the right choice for your home.

Get a Free Boiler Quote

Challenger Heating Services specialise in professional boiler installations across the West Midlands.

✔ Gas Safe Registered Engineers
✔ 10-Year Boiler Warranties Available
✔ Flexible Finance Options
✔ Five-Star Rated Local Business
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✔ Clean, Professional Installation

Call us today or request your free online boiler quote.