Installation and operating instructions for Firebull hot air stoves

Table of Contents

1. Intended use and operating principle
2. Important warnings before installation
3. Efficient dual-chamber combustion
4. Flammability of building materials and safety distances
5. Installation and assembly instructions
6. Operation and use of the stove
7. How to light the fire correctly
8. Fuel loading (safe procedure)
9. Maintenance and cleaning
10. Power regulation (damper positions)
11. Regular inspection and servicing
12. Troubleshooting (FAQ)
13. Warranty and service conditions
14. Service contact
15. Warranty exclusions (when claims are not accepted)
16. How to proceed with a claim
17. Environment and disposal

This manual is intended for the installation, operation, and maintenance of Firebull series fireplaces. The design and operating principle are identical across the entire model range.

Supported models:

• Firebull Mini
• Firebull S6, S8, S10, S12, S14, S16, S18

1. Intended use and operating principle

Firebull hot air stoves are designed for local heating and supplementary heating in various types of spaces, such as:

• Residential spaces: family houses, cottages, cabins, clubhouses.
• Commercial and public buildings: restaurants, cultural halls, greenhouses.
• Industrial spaces: production halls, warehouses, workshops, or construction site facilities.

The stoves are intended for standard environments. They must not be exposed to direct weather conditions and must not be used in explosive environments or in areas with volatile substances.

Efficient heat transfer without a fan

The unique design of Firebull stoves uses not only radiant heat from the surface but primarily natural air circulation for heating. The stove casing is formed by a system of tubes that act as an internal heat exchanger.

1. Intake: Cold air near the floor is naturally drawn into the lower part of the tubes.
2. Heating: As it passes through the tubes around the combustion chamber, the air is quickly heated.
3. Distribution: The hot air exits through the upper part of the tubes and naturally mixes with the room air.

Main advantages of this system:

• Silent operation: Rapid air mixing occurs without a noisy fan.
• Energy independence: The system requires no electricity, so there is no risk of overheating during a power outage.
• Less dust: Circulation is natural and does not cause excessive dust circulation as forced ventilation does.

IMPORTANT NOTICE: The surface of the stove and its parts reach high temperatures during operation. Always handle the stove (loading fuel, regulation) only with heat-resistant gloves to prevent the risk of burns.

2. Important warnings before installation

Before installing the appliance, carefully read this manual. It contains key information for safe and efficient operation. Keep the manual near the stove for future reference.

Inspection upon receipt

Upon delivery, check the packaging, condition, and completeness of the contents. If you have any doubts, do not use the device and contact the supplier immediately.

Safety rules

• Responsibility: Installation must comply with applicable standards in the country of use and the manufacturer’s instructions. The manufacturer is not liable for damage to health or property caused by improper installation.
• Operation: The stove may only be operated by persons over 18 years of age who have demonstrably read and understood the manual.
• Children and animals: Leaving children or pets unattended near the stove is not permitted.
• Distances and protection: Maintain prescribed safety distances from flammable materials. If protective pads or screens are part of the installation, never remove them.
• Change of environment: If conditions in the room change in a way that could lead to fire or explosion risk (e.g., handling volatile substances), stop using the stove in time.

Operation and maintenance

• Prohibition of modifications: Any unauthorized modifications to the device are prohibited.
• Repairs: In case of a malfunction, do not attempt self-repair. Always contact a qualified professional.
• Spare parts: Use only original spare parts supplied by the manufacturer.
• Do not overload the stove: Follow the recommended output. Overloading may damage internal heat-resistant plates inside the stove (e.g., due to sudden impacts of wood or excessive heat).

3. Efficient dual-chamber combustion

Firebull stoves use a dual-chamber combustion system. For proper function and maximum efficiency, three basic conditions must be met:

1. Quality fuel: Use only dry wood (max. 20% moisture). This is achieved by drying under a shelter for approximately 2 years.
2. Proper temperature: To activate efficient combustion, a temperature of 350–600 °C must be reached in the combustion chamber.
3. Air supply: Ensure sufficient primary and secondary air intake (settings may vary depending on the draft of your chimney).

4. Flammability of building materials and safety distances

When installing Firebull stoves, it is essential to consider the flammability class of surrounding materials (floor, walls, furniture). The table below classifies common building materials into flammability categories:

5. Installation and assembly instructions

When installing Firebull stoves, all local, national, and European standards must be observed (especially ČSN 73 4201/2016 ed.2).

Floor and load-bearing capacity

The stove must be placed on a non-combustible floor with sufficient load-bearing capacity. If the existing floor does not meet the requirements, a load-distributing base plate must be used.

Protective base plate (when placed on combustible material):

If the stove is installed on a combustible floor, it must be fitted with a heat-resistant and mechanically durable base plate that extends beyond the stove footprint:

• Front: at least 600 mm
• Sides: at least 400 mm

Safety distances

• From combustible materials: minimum 800 mm in all directions.
• Protective screen: If the 800 mm distance cannot be maintained, a fire-resistant screen must be used. This applies especially in cases where the surface temperature of combustible walls or furniture could exceed 100 °C.

Connection to the chimney

• Chimney draft: Minimum required draft is 12 Pa.
• Professional installation: Connection may only be carried out by a qualified professional with approval from a chimney service company.
• No sharing: The stove is not designed to be connected to a shared chimney with another appliance.

Flue pipe installation:

1. The flue pipe must be as short as possible and must not narrow towards the chimney.
2. Pipes longer than 2 m must be firmly anchored to the wall (e.g., with a bracket).
3. Individual sections must fit tightly together. Important: The lower pipe is inserted into the upper one (so-called “with the flow of smoke”) to prevent flue gases from escaping into the room.
4. Ensure access for cleaning the flue pipe and chimney sweep doors.

Air supply (ventilation)

For proper combustion, Firebull stoves require sufficient oxygen.

• Required volume: In enclosed spaces, ensure an air supply of approx. 200 m³/h.
• Air sources: In standard buildings, air leakage through windows and doors is usually sufficient.
• Warning: In rooms with the stove, the use of kitchen hoods or other exhaust ventilation systems is not recommended. They may cause chimney draft reduction and backflow of flue gases into the room.

Post-idle check: If the stove has not been used for a longer period, always check before the first firing that the flue pipes or chimney are not blocked (e.g., by soot or spider webs).

6. Operation and use of the stove

First commissioning (burn-in of the coating)

The surface of Firebull stoves is coated with a special heat-resistant paint. During the first firing, this coating is permanently cured (burned in), which is accompanied by:

• Slight smoke emission from the stove surface.
• A characteristic odor.

Recommendation: Perform the first firing before the heating season begins. Ensure intensive ventilation (draft) and temporarily remove pets from the room (especially birds and other sensitive animals).

Fuel: What to burn (and what not to burn)

Firebull stoves are designed exclusively for firewood.

• Suitable fuel: Dry logs approx. 100 mm in diameter. Hardwoods (beech, oak, birch, hornbeam) are ideal as they burn longer.
• Unsuitable fuel: Softwood (conifers) burns quickly and causes more chimney fouling.
• Prohibited fuels: Coal, coke, briquettes, sawdust, waste, liquid fuels, and flammable liquids. Using petrol or alcohol for ignition is strictly prohibited!

7. How to light the fire correctly

1. Preparation: Place 2–3 small logs at the bottom of the firebox (even on a layer of ash if present), add paper or an approved fire starter, and sufficient kindling.
2. Loading: For the initial firing, load a larger amount of wood (approx. up to half the height of the combustion chamber). This quickly heats the chimney and establishes proper draft.
3. Air supply: Open the primary air control fully.
4. Ignition: Close the door immediately after lighting.
5. Regulation: Once the fire is properly established, adjust the controls to achieve a steady, rather subdued combustion.

Warning: Excessive draft or too much fuel may lead to overheating and permanent damage to the stove. Conversely, insufficient draft (below 12 Pa) causes glass blackening and smoke leakage into the room.

8. Fuel loading (safe procedure)

To prevent smoke from escaping into the room when opening the door, follow this procedure:

1. Open dampers: Fully open the flue damper and air intake for at least 10 seconds.
2. Pressure equalization: Slightly open the door (just a crack) and wait a few seconds for the chimney draft to stabilize.
3. Opening: Only then open the door fully and add fuel.
4. Amount: Add fuel only when the previous load has burned down to a bed of embers. The door must always close easily.

How to control stove output

Stove output is regulated not only by air supply but mainly by log size:

• Thick logs: Long burning time, smaller flame, lower output.
• Thin/split logs: Short burning time, large flame, high immediate output.

9. Maintenance and cleaning

How to keep the glass clean

Glass cleanliness depends on chimney draft as well as operating technique.

• Proper loading: Place fuel in a single layer as far from the glass as possible. Leave gaps of approx. 10 mm between logs (including eco briquettes) to allow airflow.
• Self-cleaning by heat: If the glass becomes slightly soiled, open the air regulator in the door. Increased combustion intensity usually burns the deposits off automatically.
• Mechanical cleaning: Perform only when cold. Use a special fireplace glass cleaner, oven cleaner, or damp newspaper dipped in fine ash.

Ash removal

Firebull stoves have no grate, therefore ash should not be completely removed.

• Ash layer is beneficial: The remaining layer protects the stove bottom and helps maintain a temperature difference for air circulation.
• When to remove: Remove ash only when it reaches the lower edge of the loading opening.
• Safety: Remove ash only when cold. Use non-flammable containers with lids or a dedicated ash vacuum. Wood ash is an excellent fertilizer for compost.

10. Power regulation (damper positions)

For proper operation, it is important to understand the positions of the control elements:

Optimal settings for best efficiency:

For normal operation with good chimney draft, we recommend the following settings:

1. Primary air flap (door): set to 25% open.
2. Secondary air flap: set to 100% open.

11. Regular inspection and servicing

• Seals: Regularly check the sealing ropes on the door and glass. If they are brittle or leaking, replace them. Tip: After the first month of operation, check the tightening of the glass brackets (the rope compresses during use).
• Lubrication: Occasionally lubricate door hinges and moving parts of the dampers with heat-resistant grease. Always perform when cold.
• Chimney: Have chimney cleaning carried out by a professional. Keep flue pipes clean and unobstructed.

12. Troubleshooting (FAQ)

• Smoke entering the room: Check chimney draft, flue cleanliness, and whether a kitchen hood is running in the house. If the problem persists, stop heating immediately and ventilate the room!
• Stove overheating: Immediately close all air inlets and the flue damper.
• Chimney fire: Close air inlets, do not use water! Call the fire brigade immediately and have the chimney inspected by a professional after extinguishing.

13. Warranty and service conditions

Warranty period and manufacturer responsibility

The company Radek Líbal – Firebull provides a warranty of 36 months from the date of product acceptance.

• The warranty is valid only if all installation, operation, and maintenance rules stated in this manual are followed.
• During the warranty period, the product meets the characteristics specified in the technical standards and on the nameplate.
• All legal relations are governed by the Civil Code (Act No. 89/2012 Coll.). Any disputes shall be resolved by the District Court in Hradec Králové.

What is covered by the warranty?

The warranty covers free repair of defects caused by faulty materials or manufacturing errors.

The warranty does not cover:

• Normal wear and tear: Natural wear of components during use.
• Glass: Cracked or otherwise mechanically damaged glass is not covered.
• Unauthorized modifications: The warranty is void if any third-party intervention is made to the stove structure without the manufacturer’s approval.

14. Service contact

Warranty and post-warranty service in the Czech Republic is provided directly by the manufacturer. In case of doubt or malfunction, always contact us before attempting any self-repair.

Manufacturer and service center: Radek Líbal – Firebull, Lišická 881, Chlumec nad Cidlinou, 503 51, Tel.: +420 777 332 322, E-mail: info@kamnafirebull.cz

• Claim processing time: Standard processing time is 30 days from submission.
• International service: Warranty and post-warranty services are provided by local importers or contracted service organizations in the respective country.

15. Warranty exclusions (when claims cannot be accepted)

The warranty does not cover defects or damage caused by external influences or improper use. Radek Líbal – Firebull is not liable in particular in the following cases:

• Incorrect installation and draft: Errors in flue connection, insufficient or excessive chimney draft (not complying with standards).
• Incorrect power selection: If the stove is undersized (overheating of the space) or oversized (tar formation) for the given room.
• Improper operation: Overloading the stove (e.g., burning with doors open), use of unsuitable fuels, or mechanical damage caused by force.
• Structural damage: Burn-through of the deflector or deformation of the casing due to thermal overload.
• External influences: Chemical effects during transport, improper storage, contamination by spilled food, or cooling of hot stove with water.
• Unauthorized interventions: Modifications to the firebox or flue system, or use of non-original Firebull spare parts.
• Neglected maintenance: Cleaning with inappropriate agents or insufficient care of the appliance.
• Force majeure: Natural disasters (floods, fire, etc.).

16. How to submit a claim

Submit warranty claims through your dealer or directly to the manufacturer. To ensure fast processing, prepare the following:

1. Stove type and year of manufacture (found on the nameplate on the rear side of the stove).
2. Proof of purchase (invoice).
3. Evidence of the defect (photos or description of the issue).

Customer tip: Before submitting a claim, we recommend checking the “Troubleshooting” section. Many issues are caused by chimney draft or damp wood and can often be resolved without service intervention.

17. Environment and disposal

We care about the environment. Please handle waste responsibly:

• Packaging materials: All packaging falls under the category “Other – O”. They are not contaminated with hazardous substances. Dispose of them for recycling (paper in blue bins, foil in yellow bins).
• End-of-life stove: After the end of its service life, dispose of the product at a collection yard as metal waste. It is a material that can be almost 100% recycled.