How to Install an Inline Duct Fan

Many people would like to be able to increase the airflow in their duct system. Either to increase airflow, speed up heating and cooling, or to circulate air to damp places in the home. Personally, I have tried these In-line duct fans, and find them to perform minimally at best, and I would recommend using a 6" duct fan instead of a 4" fan, but if you want to give it a shot - here is how you install one.

Things You'll Need

• Duct Fan
• Ductstat Plug-In Line Voltage Thermostat
• Metal Tape
• tin snips
• drill with small metal bit

Instructions

1. 

   First of all, determine what size duct system you have in your home or office, and what type of duct work it is. Do you have a 4", 5", or 6" duct system? Is it a solid metal duct? Is it a flexible duct? Are there crimped sections that you can disconnect by taking off the duct-tape, or do screws hold the sections together. This is important because all of this, will determine what model duct fan to purchase - in different sizes and for different types of ducts for installation. Get this information first, then go and buy your duct fan.

2. Next, determine where you want to install the fan within your duct work so that you can easily access it, and so that it is also located close to a circuit breaker protected power outlet (115-120 volts only - not 220). I recommend that you install your duct fan 6 - 10 feet from the register you wish to boost air to in order to reduce noise. Always leave your duct fan accessible for maintenance, cleaning or repair.

3. Once you have accessed a good point in your duct system that is about 6-10 feet away from the register you want to boost your air-flow to and you have decided where to plug the fan in, we are going to install it.

4. Depending on the duct system you have and the duct fan you purchased, the fan will have a template in the box for use to cut out the section of your duct for installation, or you can simply disconnect your duct work and directly connect it to your fan. I am not sure what type of duct work you are working on, so this is the step that you either cut out the ducting, or simply attach it to the fan. I will assume that you are working with rigid ducting (all metal) and will have to cut out your duct work to install your fan, because I did - so here is what you do. Tape the enclosed template to the duct with the arrow pointing in the direction of the airflow.

5. Cut out the required opening in the ductwork, that the template shows, by first drilling a pilot hole through the template and into the ductwork along the dotted line.

6. We are not going to take our tin-snips and cut out the dotted lines. Cut it out completely and test the fit for your fan. Modify if needed.

7. Take your duct fan out of the box, and place it into the opening of your duct work that you just cut out. Making sure that the fan blade can turn freely, by spinning it with your finger. Also be sure to align the arrow on the unit in the direction of the airflow in your ducts.

8. Depending on the model you have, you now should only have to mount the fan in place it using the small steel screws provided with the fan, or a spring system that comes with the fan.

9. Feed your wires out through the side of the opening, and tape them against the duct using your metal duct tape. We want to get to these easily when we wire up our fan.

10. You should also now cover the seems of the fan in the duct with the metal duct tape to ensure that no air escapes in the hole you just cut.

11. If you were lucky enough to be using a duct fan for flexible duct work, or are using a duct fan that just goes into the crimped section of your ductwork - simply tape the ducting to the fan with the metal duct tape, and screw the baseplate of the fan into the duct work.

12. Now we want to run power to the fan. You can splice a plug to your fan and plug it into a 115-120 volt outlet on your breaker protected circuit with a switch so you can turn the fan on and off, or you can plug the fan into a Ductstat Plug-In Line Voltage Thermostat system. I did this, and I recommend that you do it as well as it will regulate the fan, and works great! Read the directions that come with this unit.

13. Turn on your unit and see how it works. You may see an increase in air-flow, but I personally feel that it is minimal. Hopefully it meets your needs. Be sure to clean your fan at least twice a year to keep dust and lint off of it.

Tips & Warnings

• Clean your In-Line Duct Fan along the same timeline that you would clean the fan for your furnace, but at least twice a year.

• Keep your In-Line Duct Fan free of lint, dust, and debris.

• Always leave the In-Line Duct Fan accessible for service.

• The In-Line Duct Fan must never be exposed to temperatures over 140F.