Not installed properly by home builder...Fischer Homes. Only a third of screws used, which will be addressed at 30-day Warranty inspection. When blower is on, air flows back down. Also, the two light bulbs which came with the unit are such low wattage/voltage, they are extremely dim and virtually useless. Looked on line and to get a brighter bulb the cost is ridiculous. Brighter bulbs should have been included with the unit, as the included ones are USELESS.