Review of the Koster sauna stove - design, characteristics and modifications

By power

In the marking of stoves of the “Koster” line

a numerical value is indicated indicating the maximum possible volume of the steam room for a given furnace, however, when calculating, it is necessary to take into account related factors and, as a consequence, correction factors.
Such as: 1. Quality of thermal insulation of the room. In the absence of proper reflective insulation, the actual cubic capacity must be multiplied by 1.5. 2. Material of the steam room. When calculating the volume of a room, for each square meter of surfaces made of brick, tile, concrete or glass, 1.2 m3 should be added to the volume. 3. Frequency of operation of the furnace. When operating the stove in the winter, it is necessary to multiply the resulting volume of the steam room by a factor of 1.5. According to the created microclimate. Most existing sauna stoves are divided into convection and inertial. Convection ovens quickly heat the air in the steam room, creating a sauna microclimate. Inertial stoves heat a large mass of stones with priority and release heat longer, creating a soft microclimate.

The lineup

The company producing Koster stoves is very young and so far there are few lines as such: only three, but they have a sufficient number of modifications, and the size range in two of them allows them to be used in both large and small steam rooms.

Basic line of Koster sauna stoves

This stove appeared first and it was this model that was discussed above. It is presented in five modifications, which are suitable for steam rooms with a volume of 4 to 28 cubic meters. Their technical characteristics are summarized in the table.

Technical characteristics of fireplace sauna stoves

Note! Depth indicated for model without remote tunnel. If you need an offset, add another 209 mm - this will be the depth of the Koster stove with an external combustion tunnel. The price is for the basic configuration - with a stem and a metal door.

Appearance of fireplace sauna stoves

The manufacturer offers the following options as options:

• Door with glass. Its weight is 1.5 kg, the door dimensions are 263*34*290 mm, the glass dimensions are 200*230 mm, the cost is about $40.
• Panoramic door with large glass (modification “Relax”). In this case, the door width is 440 mm, the weight is 9.5 kg (add to the original weight of the stove), the price is about $110. This door is different from those offered by other manufacturers - it is also extended upward. Therefore, even being at a distance of 1.5-2 meters from the stove, you can stand and admire the play of the flame.
• Heat exchanger register (the letter “P” is added to the marking). The register is located in the front part of the firebox, the connection fittings are on the front surface. The maximum tank volume that can be connected to this register is 60 l.
• Samovar-type tank on a pipe. The volume of this tank is 50 liters, it boils in 50-60 minutes (through the register, the water takes twice as long to heat up). Therefore, to maintain a normal microclimate in the bathhouse, it is necessary to drain hot water in a timely manner to prevent boiling and the formation of wet steam.

How to connect a remote tank to a register

Bonfire-Grid

Mesh sauna stoves are popular because of their non-standard appearance - the body of the stove is lined with stones, which are held in place by the mesh. This solution also makes it possible to reduce hard radiation from the walls of a heated firebox to a minimum - it is “intercepted” by stones. And heated stones already transfer heat gently, in a range of thermal radiation that is pleasant for our body. But this solution also has disadvantages. Firstly, it takes two to three times longer to warm up the steam room. Secondly, the walls of the firebox covered with stones overheat and burn out faster.

Screen with holes for more active heating of stones and cooling of the firebox walls

Since 2013, these problems have been solved in Koster mesh sauna stoves: additional convective screens with perforations are installed around the firebox. The air rises along the wall of the firebox, cooling it. Through the holes in the screen, it partially exits into the heater, transferring heat from the walls to the stones. This speeds up the heating of the stones and eliminates the problem of overheating of the firebox walls.

Technical characteristics of fireplace stoves Koster-Setka

As an option, you can install a mesh module on the pipe and lay stones inside it. This is also an opportunity to shield the hard radiation from the chimney, as well as to remove more heat and speed up the heating of the steam room. Agree, the appearance of this model with a mesh on the pipe is more harmonious.

Appearance of the Koster-Grid stove for a bath

This line is equipped with either a standard door with glass or a panoramic one. It is also possible to install a heat exchanger.

Koster-PaRus

Many Russian bath lovers believe that good light steam can only be obtained from stones heated in a closed heater. In this case, the steam turns out to be really light and “dry” - very small droplets contain a minimum of moisture. The Koster-PaRus stove was created for fans of closed heaters. It is currently presented in a single modification - for steam rooms from 12 to 24 cubic meters, but there are three door options - simple metal, with regular and panoramic glass. An extension for the firebox from the adjacent room can also be installed.

Technical characteristics of the Bonfire sauna stove with a closed heater PaRus

Wood burning stoves "Koster" - an informed choice

When choosing wood-burning sauna stoves, a modern buyer, as a rule, does not experience difficulties in finding a model that is suitable in terms of power. Rather, he has the problem of choosing “his” option from many possible ones.

Most focus on criteria such as brand recognition, attractive design and, of course, cost. However, these criteria do not guarantee either the durability of the product or the creation of a comfortable microclimate in the steam room. At the same time, people try to purchase a stove for more than one year and expect to get maximum pleasure from the vaping process. Is not it?

Most focus on criteria such as brand recognition, attractive design and, of course, cost. However, these criteria do not guarantee either the durability of the product or the creation of a comfortable microclimate in the steam room. At the same time, people try to purchase a stove for more than one year and expect to get maximum pleasure from the vaping process. Is not it?

Materials

Today, most manufacturers use thick-walled structural or thin-walled stainless steel in the manufacture of their products. Each of these materials has both its strengths and disadvantages.

By developing and manufacturing modern sauna stoves, the specialists of Koster Group of Companies combined the most useful qualities of both types of steel in the production of fireboxes:

Low-alloy steel 09G2S with a thickness of 4 mm is characterized by high rigidity. Due to this, the risk of deformation of load-bearing walls is minimized. This is an excellent alternative for those who would like to purchase a cast iron sauna stove, which, as is known, is not subject to deformation.

High-alloy steel 08Х17Т 4 mm thick with a scaling temperature of over 850°C is 3 times more durable than structural steel.

Design features

Being specialists in our field, we know that when choosing a stove it is worth carefully studying not so much the features of its design, but the features of its construction. And it is this issue that we paid special attention to.

By increasing the height of the firebox and making it narrower, we were able to increase the area of ​​contact of the flame with the walls of the firebox. Thanks to this, the air in the steam room heats up faster and more evenly.

In comparison with analogues, the height of the firebox manifold, in which the flame divider is located, has been significantly increased. This made it possible to solve the problem of incomplete combustion of wood and significantly increase efficiency, especially in comparison with the fireboxes of cast iron stoves, where wood combustion occurs less efficiently

The design of Koster wood-burning stoves uses a patented technical solution, thanks to which the user can switch the operating stove to combustion stabilization mode. This makes it possible to accomplish several tasks at once: increase the service life of the equipment and reduce the consumption of firewood.

Review of the Koster sauna stove - design, characteristics and modifications

Novosibirsk is rightfully considered a technical center for the design and industrial production of sauna stoves. Among the numerous manufacturing companies, the group occupies a special place. In its product range, in addition to bath stoves, you can also find heating equipment for the home. But the main activity of the company is the production of innovative stoves in its own way. The specifics of their designs and performance qualities need to be discussed separately.

Design

The differences in the Koster sauna stove are immediately visible when you first look at it.

The design has a high and narrow firebox, which allows for the most efficient use of the thermal energy of burning wood. This is achieved by increasing the area of ​​contact of the flame with the walls of the combustion chamber.

An important advantage is the unique design of the stove, which is designed for effective air convection of air flows, both in the heater area and in the steam room area.

Design Features:

• 
  The combustion chamber has a higher manifold than traditional stoves. In its upper part there is a divider, which promotes the formation of a secondary flow for the afterburning of wood gases. This significantly increases efficiency.

• Use of different types of steel, depending on the thermal load. The furnace walls are made of 2 types of steel: low-alloy steel with high rigidity and high-alloy steel, with a scaling temperature of over 850°C. This allows you to achieve good thermal conductivity and resistance to long-term thermal influences. The thickness of the plates is 4 mm.
• The vertical design promotes the most efficient transfer of heat flows to the area of ​​the heater, which contributes to its rapid heating and the formation of so-called “light” steam.
• Separate air channels ensure uniform heating of the entire surface of the stove and efficient heating of the heater made of stainless steel.

Principle of operation

After loading fuel and igniting it, the walls of the combustion chamber quickly heat up. At the same time, convection air flows begin to pass through the outer casing of the convector, heading both into the room and into the heater. At the same time, heating of the surface of the heater occurs evenly - by direct transfer of thermal energy from the combustion chamber and with the help of hot air flows. Thanks to this system, the stones are heated to the desired temperature in 30-40 minutes.

Advantages:

1. The flame burning height has been increased, which contributes to better efficiency indicators.
2. A high heating rate of the stones is possible due to their minimal distance from the firebox - 90 mm.
3. Improved air convection, which contributes to both efficient heating of the heater and the sauna room.

Flaws:

1. Relatively high fuel consumption. Increased combustion intensity requires constant loading of fuel into the firebox.
2. There is no model with a closed heater, which would be able to heat the stones more efficiently and generate steam.

The manufacturer's model range has several types of sauna stoves, which differ both in shape and technical parameters.

Bonfire

The basic design on the basis of which other sauna stoves were developed.
This model can have various modifications:

• Depending on the volume of the heated room - from 14 to 28 m³.
• Different types of combustion chamber doors - steel or heat-resistant glass.

Models with a short fuel channel will be optimal in those baths where the stove is installed entirely in the steam room, or the thickness of the wall between the steam room and the bath is minimal.

The design may also contain a built-in register, which is located on the front wall of the furnace. It is used for hot water supply to the premises. During operation, its volume should be at least half full.

For lovers of aesthetics, the company offers an enlarged glass firebox door, which will create a cozy homely atmosphere in the dressing room. This modification is called Bonfire-Relax.

Specifications

Recommended installation method

Price:

Net

The maximum possible placement of stones is possible in the Bonfire-Grid model.

Price:

Despite its still short history, the products are already in good demand among Russian consumers. This is due to a balanced pricing policy and good thermophysical performance of sauna stoves.