Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 22·2.3, 2.4, 2.5
Ventilation of appliance compartments
Appliance compartments enclosing open-flued appliances must have appropriately sized air vents. High and low level vents are needed where cooling air is required, and balanced compartments require special provisions.
An appliance compartment that encloses an open-flued appliance should be provided with an air vent(s) large enough to admit all of the air required for combustion and the proper operation of the flue.
High and low level vents should be provided where the combustion appliance requires cooling air and the appliance compartment should be large enough to enable the air to circulate effectively.
Where the combustion appliance is to be installed within a balanced compartment special provisions will be necessary. In such circumstances the manufacturer's instructions for the combustion appliance and ventilation system should be followed.
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