Age related signs of wear and tear on the existing house chimneys or the switch to a modern heating system often require relining the chimney. The operation of modern heating systems on old domestic chimneys would risk sooting because the chimney cross section for the low exhaust gas temperatures is too large and the acidic condensates in the exhaust would attack the chimney top. A fireplace relining is carried out by the introduction of single wall exhaust systems from the chimney top. The choice of the exhaust system depends on the type of fireplace. The sizing should be done by a specialist company.
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