Room-sealed pellet stove: heat for airtight, low-energy homes

What does room-sealed mean?

Every fire needs oxygen. A conventional stove takes it from the room: air is pulled in around doors and windows, burned in the stove and sent up the flue. In an older, draughty house that works, but you pay for it with cold air drawn in from outside and heat lost from the room.

A room-sealed stove has a closed combustion circuit. Fresh air arrives through one duct, combustion gases leave through another, and the fire never draws on the air you breathe. In the case of Ambelys, both ducts are combined in a single concentric flue: combustion air comes in through the outer duct, and flue gases leave through the inner one.

Why it matters in an airtight house

Modern and renovated homes are built to be airtight. Air is renewed in a controlled way by mechanical ventilation, often with heat recovery (MVHR). In such a house, a stove that takes its air from the room competes with the ventilation system and can upset its balance.

A sealed pellet stove avoids that conflict. Because Ambelys draws its combustion air through the flue, it does not depend on the air in the room and does not create cold draughts. That is why it is suited to low-energy houses and well-insulated renovations where every gap has been carefully closed.

• No cold draughts from air drawn into the room
• Works alongside mechanical ventilation instead of against it
• Suited to airtight, well-insulated and low-energy homes

A concentric flue pellet stove with a top outlet

Ambelys has a vertical concentric 80/120 flue outlet on top of the stove: an inner diameter of 80 mm for flue gases and an outer diameter of 120 mm for incoming combustion air. A top outlet keeps the back of the stove clear and gives the installer flexibility in routing the flue through the ceiling depending on what your home allows.

The exact route is always decided on site, because it depends on the layout of the room, the roof and the rules that apply where you live.

CSTB technical assessment

The room-sealed design of Ambelys has a technical assessment (avis technique) from the CSTB, the French scientific and technical centre for building. The CSTB technical assessment is a French procedure.

If you live outside France, your installer will check which national standards and building regulations apply to the installation. Contact us and we will help you with the documentation.

Installation clearances

The minimum distances to combustible materials are the same for the round, octagonal and square versions. They are small at the rear and sides, which helps if your room is tight on space.

• Rear: 5 cm
• Sides: 20 cm
• Side radiation area: 20 cm
• Front: 120 cm
• Ceiling: more than 75 cm
• Floor: 0 cm (no floor protection required by the test; national or local rules may still apply)

Installed by a qualified installer of your choice

A room-sealed stove only performs as designed if the flue is installed correctly. Schulhof Energies supplies the stove only and does not install flues, so installation is carried out by a qualified installer of your choice. Their site visit checks the stove position, the flue route, the clearances and the power supply (230 V / 50 Hz).

If you are an installer and would like to work with Ambelys, please get in touch.

Everything else Ambelys brings

Beyond its sealed design, Ambelys offers patented double combustion with 92% efficiency and fine particle emissions of 10 mg/Nm³, and it runs at 38 dB or less. It comes in three shapes and three finishes. Full details are on the Ambelys pellet stove page.