Firebird Envirogreen Slimline Combi Oil Boiler

Firebird Envirogreen Slimline Combi

The Firebird Envirogreen Slimline Combi is a compact, high-efficiency oil-fired combination boiler manufactured in Ireland. It combines central heating and instantaneous domestic hot water in one unit, making it a practical solution for properties where space is limited and a separate hot-water storage cylinder is not required.

The Slimline Combi is available in 12–20kW and 20–26kW heating output ranges. Firebird rates both models A for heating and B for hot water under its ErP classification.

Compact Firebird Oil Combi Boiler

The Envirogreen Slimline Combi has been designed to provide heating and hot water from a compact footprint. Its dimensions are approximately 855mm high × 520mm wide × 600mm deep, allowing it to fit beneath a standard kitchen worktop in suitable installations.

The compact casing is fully insulated and acoustically designed for quiet operation, while the hard-wearing exterior provides a durable finish for long-term use.

Instant Domestic Hot Water

Unlike a conventional heat-only oil boiler that requires a separate hot-water cylinder, the Slimline Combi produces domestic hot water directly through its integrated hot-water system.

Firebird specifies hot-water performance of approximately:

• 12–20kW model: up to 14 litres/min
• 20–26kW model: up to 16 litres/min

The manufacturer’s published figures are based on a 120-litre draw-off at a 40°C temperature differential.

Firebird also highlights rapid reheating after hot-water draw-off, making the Slimline Combi particularly suitable for smaller households and properties with a single bathroom or shower/ensuite.

Firebird Envirogreen Slimline Combi Features

• Condensing oil-fired combination boiler
• Central heating and domestic hot water in one appliance
• Available in 12–20kW and 20–26kW models
• A-rated ErP heating efficiency
• B-rated ErP hot-water performance
• Instant domestic hot water
• HVO-ready Envirogreen technology
• Compact design suitable for restricted installation spaces
• Fits beneath a standard kitchen worktop in suitable installations
• Twin circulating pump
• No diverter valve required
• Electronic water-flow detection
• PCB controller with accurate thermistor control
• Rapid hot-water reheating
• Patented heat exchanger design
• Fully insulated casing
• Acoustic design for quiet operation
• Multi-directional flue options
• High-performance low-NOx Elco burner
• Optional condensate pump
• Optional timer controllers

Available Models

Both models measure approximately 855mm high × 520mm wide × 600mm deep.

Firebird Slimline Combi for Space-Saving Installations

The Slimline Combi is designed for installations where available space is restricted. Combining the boiler and hot-water production into a single appliance eliminates the need for a separate domestic hot-water cylinder.

Its compact dimensions, integrated twin-pump arrangement and electronic flow detection help create a streamlined installation while maintaining heating and hot-water performance.

Condensing Oil Boiler Technology

The Envirogreen range uses Firebird’s patented heat exchanger design together with a high-performance low-NOx Elco burner. The boiler is fully insulated and acoustically designed to help minimise operating noise.

The Envirogreen range is also identified by Firebird as HVO ready, providing compatibility with the manufacturer’s HVO-ready oil boiler range.

European Supply

Euro Fuel Supply supplies heating and energy equipment for customers across Europe, including homeowners, heating installers, contractors, developers, trade customers and wholesale buyers.

The Firebird Envirogreen Slimline Combi is a strong option for customers looking for a compact oil-fired combi boiler with instantaneous hot water, particularly where installation space is limited and a separate hot-water cylinder is not required.

Firebird Envirogreen Slimline Combi FAQ

What is the Firebird Envirogreen Slimline Combi?

The Firebird Envirogreen Slimline Combi is a condensing oil-fired combination boiler that provides both central heating and instantaneous domestic hot water from one appliance.

What output sizes are available?

The Slimline Combi is available in two output ranges: 12–20kW and 20–26kW.

Is the Firebird Slimline Combi A-rated?

Yes. Both Slimline Combi models have an A ErP rating for heating. Firebird lists the hot-water ErP rating as B.

Does the Firebird Slimline Combi provide instant hot water?

Yes. The Slimline Combi combines central heating with instantaneous domestic hot-water production. The manufacturer lists hot-water performance of up to approximately 14 litres/min for the 12–20kW model and 16 litres/min for the 20–26kW model.

Does it require a separate hot-water cylinder?

No separate domestic hot-water storage cylinder is required for normal combi operation because hot water is produced directly through the boiler’s integrated hot-water system.

What is the difference between the 12–20kW and 20–26kW models?

The primary difference is the heating output range and associated hot-water performance. The 12–20kW model is rated up to 20kW heating output, while the 20–26kW model is rated up to 26kW.

What are the dimensions?

Both Slimline Combi models are approximately 855mm high × 520mm wide × 600mm deep.

Is the Firebird Slimline Combi suitable for small properties?

Yes. Firebird specifically describes the Slimline Combi as particularly suitable for smaller households, including properties with one bathroom or a shower/ensuite.

Is the Firebird Envirogreen Slimline Combi HVO ready?

Yes. Firebird identifies the Envirogreen Slimline Combi within its HVO-ready oil boiler range.

What type of fuel does the boiler use?

The Envirogreen technical documentation specifies 28-second Class C2 kerosene for the oil-fired boiler range.

Is this the same as the Firebird Slimline Systempac?

No. The Slimline Combi is a combination boiler designed to provide instantaneous domestic hot water, while the Slimline Systempac is a system boiler with integrated system components and is used with a separate hot-water storage cylinder.