Back draft shutters for circular ducting stops the movement of air if the extraction is off. There are two metal flaps that are held closed by springs. When the fan is extracting through the shutter, the force of airflow opens these flaps to allow the air through As soon as the fan turns off, the springs in the shutter overcome the force of air and the shutters close. Extraction systems should be run continuously to provide the plants with an exchange of fresh air, giving the best environmental chance. There is always the possibility of a fan failing or a power cut that could affect your extraction system. If a back-draft shutter is attached to the extraction, air will be stopped from escaping the area, along with unwanted smells. Ventilation for plants should be running 24/7, but in some circumstances fans may be on a timer like when air cooled fixtures are used. Back- draft shutters can prevent air from being drawn the wrong way through your air cooled fixtures when the fans go off, while still allowing the fan connected to the carbon filter to run. Durable and strong; our backdraft shutters are manufactured by Lindab in the UK to EU standards. High quality welds and mastic means no air leaks. How to Use: Install the shutter at the end of your extraction, making sure the shutter and fan airflow direction are matched. The shutter is easy to install on flexible ducting, just fasten them with worm clips to ensure an airtight fit. If you are installing the shutter on a rigid section, you can use a female coupler (straight) to connect the sections. A female coupler is wider than the equivalent ducting and shutter, so the ducting and shutter can slide into the female coupler, this joint can then be sealed with aluminium tape. Make sure you install the back draft shutter the correct way around as the shutter will be permanently closed if facing the wrong direction; Leading to a loss of air movement.
