Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 25·2.17(b)
Extract fan rate limits for oil appliances with open-flued combustion
For rooms with open-flued oil appliances, extract rate must not exceed 40 litres/second for pressure jet burners or 20 litres/second for vaporising burners. When spillage or draught interference occurs, additional ventilation may be needed and testing per OFTEC Technical Books 2 and 5 should be carried out.
for oil appliances – where a room contains an open-flued appliance the extract rate should be limited to 40 litres/second for an appliance with a pressure jet burner and 20 litres/second for an appliance with a vaporising burner. When spillage or flue draught interference is identified, it may be necessary to add additional ventilation to the room or space. A flue draught interference test for oil-fired appliances as described in OFTEC Technical Books 2 and 5 should be carried out.
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