With an extractor fitted, doors closed, the house fitted with a good draught proofing system and the air being extracted from the room at a measured rate, consideration should be given to air replacement. 'Short Circuiting' is a situation, where the air that is being removed, cannot be replaced at the same rate, resulting in the extractor loosing its ability to extract and function effectively. To overcome this problem, adequate air vents should be installed, which will allow constant air supply into the house/rooms, while the extractor takes the unwanted air outdoors.
Thought should be given to the position of air vents in relation to the point of extraction and should be fitted in strategically positioned locations that would benefit the overall air flow/ventilation system. This is best done by placing air vents on the opposite side of the room to where the extractor is located, close to the bottom of an internal door to the kitchen for example. Not only does this provide the necessary air replacement, it also benefits air circulation to the whole room, by drawing the air across it.
