Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 58·4.11
Gas point sizing for flueless appliances
A room with a gas point intended for flueless appliance use must have ventilation calculated on the basis of the largest appliance rating consistent with Table 4.1 that could be installed.
A room containing a gas point intended for use with a flueless appliance (such as a cooker, or space heater or water heater, with the gas point not adjacent to a flue) should have the ventilation provision calculated on the basis that an appliance with the largest rating consistent with Table 4.1 could be installed there.
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