Installation Guide


Fresair S7i

Below we’ve documented all the information you’ll need to install your Fresair DIY style. You’ll find a digital copy of the owner’s manual, a parts list, recommended tools to use as well as step-by-step installation customized specifically for van conversions.

Included Parts

How to Install

Please read the instructions thoroughly prior to installing the Fresair unit. We are not responsible for damages and/or improper installation due to user error. 

Step 1 – Tracing the Mounting Template

Prep Tip: It is very important that the roof surface is clean to ensure a weather-tight seal between the base of the Fresair unit and your roof. Take time to determine where you wish to install your Fresair. Ensure that the unit is placed between roof support bars so you don’t compromise roof integrity. Plan how the internal harness will run to power and reservoir.

What you’ll need: Cardboard Mounting Template, *Masking Tape, *Permanent Marker

  • Place the Cardboard Mounting Template over the exact roof area where you plan to mount your Fresair Unit. 
  • Ensure the larger notch (side A) is positioned toward the front of the vehicle and the Cardboard Mounting Template is placed between roof supports. 
  • *We recommend taping the Cardboard Mounting Template to the roof to eliminate movement while tracing the outline and hole cutouts for bolt placement. 
  • Simply trace the open area of the Cardboard Mounting Template. 
  • *We recommend using a permanent marker so the outline is clearly visible.
  • Once the outline has been drawn, remove the template (and tape.) 

IMPORTANT: For Van Conversion you do not need to cut the exact template shape. For ease you should just cut an opening of 14.5” wide (side to side of roof) and 13” tall (front to back of roof).

Step 2 – Cutting the Opening for the Fresair Unit

Prep Tip: In order to keep the vehicle free from debris, we recommend temporarily securing a plastic drop cloth around the cutout area inside the vehicle so that debris will land inside of the drop cloth and not in your vehicle.


What you’ll need: Angle Grinder/Jigsaw (Cordless tools are strongly recommended), File, Sealant/Anti-Rust Paint, *Plastic Drop Cloth, *Safety Glasses

  • Make sure to wear appropriate safety gear to protect yourself from sparks, metal ricochet, etc. such as safety glasses, gloves, long sleeves, etc. 
  • Cut the opening of 14.5” wide (side to side of roof) by 13” tall (front to back of roof) along the outline as closely as possible.
  • File any newly cut edges and ensure edges are smooth to the touch.
  • Seal the newly cut edges with anti-rust paint or sealant and allow to dry for the recommended time.
  • Clean away any remaining debris from the roof to prevent rust. 

Step 3 – Testing the Fit

What you’ll need: Fresair Unit
  • Test the fit of the Fresair Unit by lowering it in the area you’ve just cut out and make any necessary adjustments accordingly. Be careful not to crimp or damage the water hoses.

Step 4 – Adhering the Sealing Foam Tape

What you’ll need: Fresair Unit, Sealing Foam Tape

  • With the unit still in place and secure, use a permanent marker to draw an outline around the outside base of the unit on the roof. 
  • Remove the unit from the roof and turn the unit over.
  • Stick the thicker sealing foam tape around the airbox up to the honeycomb plastic line. Cut the sealing foam tape to the correct length ensuring there are no gaps where the sealing foam tape ends meet. (See figure 3)
  • Stick the thinner foam on the roof along where you traced the outside of the base. Overlap the outline slightly to ensure a conservative amount of foam sticks out from the base of the unit. Again, cut the foam to length ensuring there are no gaps where the ends meet.
  • Apply a single bead of silicone along the middle of both the foam on the unit and the foam on the roof.
  • Carefully lower the unit back onto the roof being careful to align the bolt holes first so the foam and silicone form a weathertight seal.
  • At the same time, make sure to bring wiring and tubing through the opening on the predetermined side the wiring and tubing will run to meet their connections.

Step 5 – Mounting the Fresair Unit

What you’ll need: Fresair Unit, Mounting Bracket,2 Finishing Frame Screws, *Screwdriver, *Crescent Wrench(es), *Self-leveling lap sealant/Silicone  

  • Inside the vehicle, secure the unit by attaching the mounting bracket onto each bolt, followed by a nut.
  • Tighten each of the 4 nuts gradually and evenly until the sealing foam tape compresses evenly over the roof lines or ridges. 
NOTE: Be careful not to over tighten the bolts as this can warp or crack the base.
  • Inspect how well the foam has compressed over roof ridge lines. If there are any gaps you need to run self leveling lap-sealant around the outside of the base and outer edge of the sealing foam tape and onto the roof for a better weatherproof seal. Please allow for drying time so as not to remove any of the seal. 
  • Attach the finishing frame inside the vehicle using the two finishing frame screws (This step can be skipped if you are building custom trim to match your vehicle’s interior.)

Step 6 – Electrical

What you’ll need: Supplied Electrical Wiring, *Screwdriver

  • Please remember to take any safety precautions when working with electrical wire. We recommend disconnecting the main power supply until the wires are connected for safety purposes.
  • Run the electrical wiring from the unit to the 12V DC fuse block ensuring it is completely concealed so that the wire is not exposed to elements or incidental damage. 
  • Connect the positive wire (red) to the positive terminal of your fuse block.
  • Connect the negative wire (black) to the negative terminal of your fuse block.
  • Ensure both wire connections are tightened properly and completely secured to the fuse block.
  • Next, test the power (using the Fresair power button on the unit) to ensure your unit turns on.

Step 7 – Plumbing

What you’ll need: Supplied Water Lines/Tubes, Zip Ties, Water, *Plumbing tape

    • Using the provided mounting brackets, mount the reservoir in the desired area.
    • Run water lines/tubes to the fill area. The return water line is marked with a small red dot at the end.
    • Test the connections by lightly pulling them to ensure the connection is secured.
    • Connect the electrical connectors to the float sensor and injection pump. 
    • Once you’re ready, fill your reservoir with water and seal with the provided cap. 
    • Finally, power on your Fresair and ensure there are no leaks. 
    • Additionally, test all functions to ensure your Fresair is working properly.


    NOTE: There are many ways that you could plumb up the reservoir to be filled from the main freshwater tank which is beyond the scope of this manual. The simplest installation described here assumes that you can access the filling cap with a hose.