The Onyx Athos 5 Wide Multi-Fuel Stove is a premium heating appliance designed to merge the character of classic cast iron stoves with the performance, clarity, and efficiency expected from cutting-edge 2025 combustion technology. Its wide-format body creates an expansive, cinematic flame view, delivering exceptional presence in any interior while maintaining outstanding fuel economy and ultra-clean emissions.

Crafted with a sculpted cast iron door featuring refined moulding lines, curved edges, and a deep matt finish, the Athos 5 Wide introduces a distinguished heritage aesthetic inspired by traditional British stove making. Its robust steel body ensures long-term durability, while the premium anodised handle—with a tactile knurled grip and champagne-accented end caps—adds a considered, high-end design detail that enhances both form and function.

The panoramic wide viewing window is engineered for a clear, immersive flame experience. A high-performance Airwash system keeps the glass clean for extended periods, ensuring uninterrupted visibility of the tall, lively flames that fill the wide fire chamber. This model’s enhanced convection system circulates heat evenly throughout the room, reducing warm-up times and creating a more comfortable environment for both modern open-plan homes and traditional living rooms.

Inside, the Athos 5 Wide utilises advanced multi-fuel combustion for efficient burning of both seasoned logs and approved smokeless solid fuels. A nominal heat output of 5kW, with a flexible operating range of 2.5–7kW, makes it an ideal choice for a wide variety of spaces. Its 79.5% efficiency rating and A energy classification demonstrate exceptional performance, delivering high heat with reduced fuel usage.

Unique to the Athos Wide models is an additional primary air control, allowing precise regulation of airflow beneath the fixed grate. This ensures clean, reliable combustion—especially beneficial when burning smokeless fuels or when re-establishing the fire after refuelling.

Cleanburn technology introduces tertiary air to re-ignite unburnt gases, resulting in lower emissions and a hotter, more efficient burn. Fully Ecodesign compliant and DEFRA approved, the stove is suitable for both rural homes and properties within Smoke Control Areas.

Installation flexibility further enhances its appeal. The Athos 5 Wide is compatible with a 12mm non-constructional hearth, allowing placement in more modern settings, and it can be connected to an external air supply for sealed-combustion installations—ideal for new-build homes or energy-efficient renovations.

Built to the exceptional standards associated with Onyx appliances and backed by a comprehensive 10-year warranty, the Athos 5 Wide stands out as a refined, highly efficient multi-fuel stove that brings together timeless craftsmanship, advanced clean-burning design, and a commanding panoramic flame view. It is a statement centrepiece for homeowners seeking both traditional charm and modern performance.

Features & Benefits

• Wide panoramic window: Expansive flame view enhances room ambience.
• Cast iron door detailing: Traditional craftsmanship with premium finish.
• Steel body construction: Durable, long-lasting heat performance.
• Anodised premium handle: Improved grip with refined accents.
• Heat output nominal: 5kW: Ideal for standard to medium-sized rooms.
• 2.5–7kW output range: Flexible warmth for varying conditions.
• Convector heat system: Faster warm-up and even heat distribution.
• 79.5% efficiency rating: Lower running costs and reduced fuel use.
• True multi-fuel capability: Burns logs and smokeless solid fuels efficiently.
• Additional primary air control: Enhanced control for smokeless fuel burning.
• Fixed grate system: Optimised for consistent multi-fuel combustion.
• Cleanburn technology: Reignites unused gases for cleaner, hotter burns.
• Advanced Airwash system: Helps keep the wide glass panel clear.
• Ecodesign compliant: Meets the latest emissions and efficiency standards.
• DEFRA Smoke Control approved: Suitable for urban Smoke Control Areas.
• Low emissions engineering: Cleaner burning for a more eco-conscious home.
• 12mm hearth compatible: Increased placement flexibility in modern homes.
• External air supply option: Ideal for sealed or high-efficiency properties.
• 10-year warranty: Long-term peace of mind and product confidence.