FAQ

The main questions about stoves and heating at a glance.

How do I find the right stove for me?

Choosing the right stove is partly a matter of personal taste. It’s best to discuss the technical, structural and user-specific parameters with a specialist dealer or stove installer in your local area. He will also be able to visit your home to look at your particular installation conditions.

What type of stove is best for me?

SPARTHERM can supply a full range of stove options, from fireplace cassettes for retrofitting in an existing open fireplace to our ebios-fire bioethanol burners, which produce no smoke and don’t need a chimney. There’s a SPARTHERM heating unit that’s right for you – optimised for passive homes or with maximum output to heat the whole house.

Which fuel should I choose?

The choice of fuel is very important and it depends very much on how you are going to use your stove. If you want your heating unit to burn for long periods and create a cosy atmosphere and if you have access to good quality firewood, then you should choose a wood burner. If storing and carrying logs and stoking the fire is too difficult for you, you may prefer a pellet, gas-fired or bioethanol system.

What structural conditions do I need to think about?

Apart from our ebios-fire products, which burn bioethanol, you need access to a chimney that meets the technical requirements for our products. The chimney must be approved as suitable by your chimney sweep. With regard to installation of your stove, the general installation instructions should be followed, such as minimum distances from combustible walls and placing it on a non-combustible base. For passive homes we recommend units with low kW values or appliances with an external combustion air supply (room air sealed), or perhaps a unit that also heats the water. Talk to your passive home builder about the various specifications that apply and consult your local specialist for advice.

What kW value should I choose?

The kW value indicates the output of the unit and how much radiant heat it emits. This is a value under test conditions which relates to the conditions in the particular country. The actual heat output depends on the amount of wood that the individual user puts on the fire. The size of the room also plays a big part in establishing a comfortable temperature and air quality. If you choose a unit with too low an output, the room will not be warm enough, and with too high an output, the air will soon start to feel overheated. Thermal storage stoves, no matter whether water or natural stone is used as the storage medium, will absorb a lot of energy when the stove is first lit. A slightly higher kW value can be allowed for units of this type.

Which models are suitable for passive homes?

Less is more. To be on the safe side in the case of a passive home, SPARTHERM can supply units with a low kW value and recommends room air sealed units with a separate external air supply for optimum thermal output. Alternatively, why not install the Quadra Inside automatic burner by ebios-fire. As a general rule, the better insulated a building is (passive homes), the lower the kW value that should be selected. If you have any other questions, contact the passive home builder and your local specialist.

Where can I see the stoves?

Use our Dealer Search to find a dealer in your local area you can talk to in person. Our specialist dealers have a wide range of SPARTHERM products to show you.

What does primary and secondary air mean?

Every SPARTHERM heating unit has two paths for air for combustion entering the fire chamber – the primary air flow (bottom air) and the secondary air flow (top air). When the fire starts to burn in the lighting phase, the maximum primary and secondary air flow is delivered to the stove. Then, in the subsequent course of burning, it receives secondary air only. SPARTHERM products enable the air supply to be controlled with precision.

What types of thermal storage medium are there?

The thermal storage medium ensures the fuel is used as efficiently as possible. You have a choice of natural stone, water or storage granules. In view, or out of sight. Just as you want.

What minimum installation depth do I need to install a fireplace insert?

We have created optimised units for installation situations where space is critical. Our compact units can be identified by the GET designation, indicating a shallow installation depth.

What are room air sealed stoves?

SPARTHERM heating units can be operated as a room air sealed version with an external combustion air supply and they are approved by Germany’s DIBt (Deutsches Institut für Bautechnik) for room air sealed operation in connected rooms (air inlet, flue gas duct, stove). Our room air sealed units are very effectively sealed and are able to withstand a negative pressure of up to 8 Pa. This technology enables us to guarantee safe combustion while ventilation systems such as extractors are in use, without needing additional safety devices. In room air sealed operation, the air supply for combustion must be led into the unit from an external source, via airtight pipes. 

What add-ons are available?

From the dust particle separator to additional storage medium or an elegant frame and the fitting of customised units, SPARTHERM has everything you need for your ideal stove.

What do I need to know about the chimney?

Each chimney is different, and depends on the location and even the weather. As the hot air rises up the chimney, it creates a negative pressure in the fire chamber and that helps to draw in the air needed for combustion. The chimney and the stove or fireplace must be optimally coordinated for good combustion. For personal advice, talk to your chimney sweep.

What per kW wood consumption should I expect?

Less than you think, because SPARTHERM products are all about quality and high efficiency. With one kilogram of dry firewood you can achieve a thermal output of about 3 kW, depending on the type of wood. The nominal output indicated by SPARTHERM on the rating plate is a minimum thermal output established in a test according to DIN. The heat output depends on the quantity of fuel burned and the combustion air supply. 

What do we need to be mindful of as regards the quality of the firewood?

Untreated wood is best for burning in a stove. Wood from deciduous trees like beech, oak or birch has a high energy value and is therefore ideal for burning in stoves. It burns more steadily and creates less noise when burning than coniferous wood. Make sure your firewood has been properly dried and the maximum residual moisture level does not exceed 20%. This is essential for clean burning and a high energy yield.  

Can I retrofit a particle separator to my stove?

Although SPARTHERM products already meet the strictest emission limit regulations, we can supply an accessory for this requirement if desired. To further enhance the quality of life, or to comply with a legal requirement, SPARTHERM can supply the Airbox, which is combinable with more than 30 models.

What does efficiency mean in everyday operation?

The efficiency of a heating unit describes the way the energy supplied by the fuel is converted into usable thermal energy. To put it simply, the greater the efficiency, the more heat for you.

What is an airwash?

The combustion residues that occur in a heating unit during the combustion process can form a coating on the viewing pane. To prevent this, SPARTHERM designs the heating units so that the windows remain largely soot-free. The airwash blows heated secondary air over the inside of the glass, where it creates a permanent air flow that keeps the glass clean. 

What’s the difference between radiant heat and convective heat?

Radiant heat is the heat you feel directly on your body as you approach the stove, whereas convective heat warms the air in the room evenly to create a comfortable atmosphere. Convective heat is the result of the air in the room being constantly circulated. Cooler air is fed to the stove from below, bypassing the fire chamber. The air heats up as it passes through the stove before exiting again from the top of the unit to warm the room. Materials like soapstone, sandstone, ceramic or natural stone increase the continuous heat exchange and carry on doing so for some time even after the fire has gone out.

What safety features does SPARTHERM provide?

SPARTHERM heating units are equipped with a number of safety features for trouble-free enjoyment of the fire. Our SMARTCLOSE mechanism to ensure the door is tightly closed is just one innovative safety solution from SPARTHERM. Another safety aspect: SPARTHERM products are only available from approved specialist dealers. The sound advice our dealers provide to customers in person gives you the assurance that your heating unit will be correctly planned and installed. 

Pane soiling with wood fireplaces