Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 58·Examples
Example calculations for flueless space heater ventilation
Two worked examples demonstrate how to calculate maximum appliance ratings and required vent areas for space heaters in different room types.
Examples:
a. Space heater in a lounge measuring 4 m x 4 m x 2.4 m = 38.4 m³, the appliance rated input should be not greater than 38.4 x 0.045 = 1.73 kW.
b. Space heater in a hallway with a rated input of 7 kW (net) should have a permanently open air vent with a free area of 10000 + 2750 x (7 - 5.4) = 14400 mm².
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