These liners are double skinned, with a smooth inner surface. This makes it more difficult for soot and tar to adhere, making sweeping easier, thus reducing the risk of chimney fires.
Flexible liners are made of 316TI or 904 stainless steel. 316 (TI) liners have been available for over twenty years. This is a corrosion resistant stainless steel, which in normal use has proved to be satisfactory, especially on wood. Liners constructed from 904 grade stainless steel have enhanced corrosion resistance from the chlorine and sulphur attack possible from solid fuel. This is especially important if the fuel is wet and if it is burned at the relatively low temperatures possible when a fire is slumbering, without first bringing the fire up to the correct (high) operating temperature required to achieve efficient combustion. 904 grade liners will not stand as high temperatures as 316 liners in a chimney fire before they start to degrade.
Our flexible liners carry a ten-year manufacturer’s guarantee against failure due to manufacturing defects. These guarantees do not include failure due to chimney fire or due to corrosion. The fire/appliance must have been operated correctly and the chimney must be regularly swept and maintained.
Plastics and other such material should not be burnt. For more details see
manufacturer’s warranty conditions.
We therefore recommend a 316 liner be used for wood burning or multifuel stoves for secondary heating ie evenings and weekend use.
- Stainless steel liners are a short/medium term solution for lining existing chimneys only, which can be installed in most situations without having to break holes into the chimney in bedrooms or lofts, saving much expense and disruption in your home.
- Chimney fires should be avoided as they can destroy the liner due to flame impingement and/or excess temperature therefore regular sweeping and maintenance is essential.
- Insulating the void around the liner with vermiculite or leca will keep the flue gas temperature higher, thus minimising soot and tar deposits and condensation. The chimney will also be easier to clean. Both these factors will reduce the risk of chimney fires. Insulating around the liner is particularly important if the chimney is on an external wall, or if the appliance is going to be run at low temperatures for long periods. eg overnight. Insulation also keeps the heat away from any residues of soot or tar on the inside of the original chimney, helping to prevent these catching fire.
- The chimney must be thoroughly cleaned before lining.
- The flexible liner should not be connected directly to the appliance.
- The liner should be installed the correct way up, following manufacturer’s instructions and meeting any current building regulations.
please note: all installations must be fitted by a qualified Hetas engineer or with building regulation approval.