While it’s not a legal requirement, using a fuel liner is highly recommended when installing a multi-fuel stove. A flue liner is a flue or chimney lining that ensures proper venting of combustion gases and helps prevent dangerous emissions, such as carbon monoxide, from entering your living space. A fuel liner will increase efficiency, help keep your chimney clean and improve safety.
Your wood burning stove needs to meet the building regulations listed in Document J, which recommends (but does not require) that flue liners are used.