OKO S1 Bio Ethanol Stove in Charcoal Grey

Frequently Asked Questions

•  Can I add decorative logs or cover the burner ?

  Do not obstruct the burner opening or the aperture. Under no circumstances, place ceramic logs or decorative items inside or around the burner.

•  What fuel should I use ?

  Use high purity liquid bio ethanol (≥96%) designed for indoor fireplaces.

•  Do I need a chimney or a flue ?

  No these are flueless decorative appliances. Ensure minimum room volume and ventilation stated on the product page/manual

•  What run time should I expect ?

  3–5 hours for 1.5 L burners Up to 8 hours at reduced aperture.

•  What output (kW) can I expect ?

  Commonly quote up to ~2.3–3 kW depending on aperture

•  What about odor, CO₂ ?

  Bioethanol combustion is clean, but it still uses oxygen and produces CO₂ and water vapor, so proper ventilation is essential. Always follow your model’s minimum room volume requirement ensure the room has a fresh air supply. A slight odor may be noticeable when lighting or extinguishing, which is normal. Using a CO alarm in the same room is recommended as a general safety practice.

•  Are bio ethanol fires suitable for people with lung disease or sensitivities ?

  They consume oxygen and produce CO₂ and water vapour (plus trace by products). If you have respiratory conditions, consult your clinician first. Always ensure good ventilation, avoid long runs in small rooms, and stop use if you feel irritation.

•  How much fuel should I add ?

  Never exceed the maximum fill level specified in your model’s manual. Overfilling increases the risk of flare‑ups and makes the burner harder to extinguish. When refilling or topping up: Only add fuel when the flame is fully extinguished and the unit has completely cooled down. Never pour fuel onto a hot or active burner.

•  I hear “popping” sounds. Is that normal ?

  Occasional soft pops can occur from vapor changes. Loud, repeating pops or pops accompanied by flame surges indicate a draft/fuel issue or abnormal combustion document with video and contact support.

•  Why does condensation appear inside the glass door ?

  Condensation appears because the OKO S1 releases water vapor during combustion, which settles on the cooler glass surface especially at startup or in rooms with limited airflow. The recommended solution is to improve ventilation by opening a window, vent, or internal door so the moisture can disperse naturally and reduce build‑up otherwise the condensation should disperse naturally as it heats up.

•  How do I extinguish the flame?

  Use the supplied control tool to close the aperture/closing plate fully; never add water. Wait until the burner is fully cool before refueling.

•  What room size do I need?

  Always follow the minimum room volume specified in your model’s manual. As a general guideline, ensure the room is at least ~63 m³. Adequate room volume is essential because bioethanol combustion uses oxygen and produces CO₂ and water vapor, so the space must be large enough to maintain safe air quality. The room should also have some form of ventilation, such as an open vent, trickle vent, or occasional window opening.

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