Newly developed liner in the product range of Kompozitor Kft.: FuranFlex^® HHR

With the support of the National Research, Development and Innovation Office, Kompozitor Kft. has
developed a new, highly fire-resistant chimney liner prototype for the use of solid fuels. The new
product under the brand name of FuranFlex^® HHR (High Heat Resistance) is suitable for lining
chimneys exposed to higher heat loads and aggressive condensate condensation, for wood, pellet or
coal-fired boilers. The development was necessary because the chimney lining systems available on
the market are difficult to withstand the double effect that occurs during the burning of this type of
fuel. Either they withstand the corrosive effect of the precipitation that condenses in the chimney
during the operational load, but they are not adequately heat resistant, or they are adequately heat
resistant, but they do not withstand aggressive moisture. Kompozitor Kft. also has a product, the
FuranFlex^® RWV composite synthetic resin chimney lining system, which has adequate heat resistance
for wood burning in dry mode for the safe evacuation of flue gases, but for example the aggressive
condensate produced by burning pellets (wet mode), it cannot sustain operating temperature
maximums of up to 600 °C or higher. The development of the efficiency of the heat exchange
elements that are part of modern boilers further increases the risk of the condensation phenomenon
occurring on the chimney wall by reducing the temperature of the flue gases leaving the system.
Thanks to this, the condensation phenomenon in the chimneys also increases when other solid fuels
are used, which results in an increased corrosion effect of aggressive precipitation on the inner side
walls of the chimney.
The newly developed FuranFlex^® HHR chimney lining composite synthetic resin chimney liner for solid
fuel combustion systems provides a solution to these problems. As a result, the objectives and
expected technical parameters for its development were as follows:
- Higher heat and flame resistance. The permanent (lifetime) heat resistance of the lining pipe should
be above 600 °C, but it should also be able to withstand the extremely high heat load of 1300 °C for
30 minutes, which is important due to fire safety regulations.
- Better moisture and corrosion resistance. The new product should resist the aggressive condensate
that leaves the combustion chamber with the smoke when solid fuels are burned and settles on the
side walls of the chimney.
- Long service life, which is unprecedented for solid fuel chimneys.
- Easy to install, which is a serious competitive advantage for the new product compared to
competitors (steel, ceramic chimney lining systems).
- The new fireproof chimney lining pipe can only contain boron compounds as a flame retardant
additive to a reduced extent in order to meet the strictest environmental protection requirements.
The new development of Kompozitor Kft. was based on the already successful FuranFlex^® technology.
The essence of this is the installation method, where the composite lining pipe is pulled into the
existing chimneys in a soft, folded form and then placed under hot steam pressure. As a result of the
steam pressure, the soft composite pipe is stretched over the inner side wall of the chimney, takes
on its surface form, and then hardens irreversibly, thus lining it airtight from the inside, providing
adequate surface protection for the masonry structure. The hardened chimney liner perfectly follows
the changes in direction and pulls of the flight, taking its shape. A composite compound

corresponding to this technology had to be developed, which fulfills the parameters defined at the
beginning of the development.
The development of Kompozitor Kft. was successfully completed, resulting in a new product under
the brand name FuranFlex^® HHR (High Heat Resistance). The new chimney lining technology can
sustainably and safely withstand the strong stresses resulting from the characteristics of solid
combustion, the higher, in extreme cases, operational heat load reaching 600 °C and possible
aggressive condensate condensation. At the same time, its installation is simple and the price is
favorable.
By using the developed product, the chimneys can become suitable for the safe removal of flue gas
produced when burning all kinds of solid fuels. The high corrosion, heat and flame resistance ensures
that the product is durable in normal operating environments, but protects residential property and
human life even under extreme stress, such as a chimney fire.